Speedometer doesn't work and transmission doesn't shift gears.

915

Asked by dfrinzi Nov 25, 2011 at 07:33 PM about the 1999 GMC Sierra 1500 SLT 4WD Extended Cab LB

Question type: Maintenance & Repair

The speedometer stays at 0 all the time.  When the transmission is in drive it won't come out of 1st gear.  Reverse works fine, and if I manually put the transmission in 1st or 2nd it works fine.

1999, Auto 4wd, automatic, 5.3L

84 Answers

1,445

Vehicles transmission output speed sensor faulty

110 people found this helpful.
Best Answer Mark helpful
915

I replaced both output speed sensors, and also swapped them around with the old ones, no luck. This problem started after I removed the transfer case to install the wear plate and replace the actuator motor, not sure if that has anything to do with it. The 4wd works fine. Thanks

91 people found this helpful.
1,185

It's Vacume or electrical is your problem or passing gear cable.If the passing gear cable is broke,unhooked at the throutle body or unhooked inside the transmission would cause that as well.Yep,Vacume could be if your 4wd works under vacume hoses or lines.If your 4wd is electric .You either got a vacume line crossed/wrong.Or leak in a vacume line or unhooked.It's not a speed sinser.Transmission Shifts either from Vacume or electrical.Sounds like to me from playing around with the transfer case you made a mistake.

58 people found this helpful.
1,440

2003 Sierra-My truck is doing the same thing- speedo reads zero and won't shift out of first. I cleaned the MAS, replaced shift sensor, made sure trans fluid was full, disconnected and reconnected the battery, and now I am thinking of replacing the stepper motors for the speedo but don't think that covers the shifting issue. ANY HELP welcome!

144 people found this helpful.
2,045

vehicle speed sensor,on the rear of the transfer case ,if you got no speed o your truck wont change gears

121 people found this helpful.
1,330

I replaced the vehicle speed sensor VSS then unplugged the vehicle speed sensor buffer VSSB (a 3 inch square flat white plastic sensor box) located behind the glove box, I unplugged it and waited 5 minutes before plugging it back in. I also pulled the brake fuse and did the same thing, waited 5 minutes then plugged the fuse back in. The result was successful, the tranny and speedometer work correctly now!

133 people found this helpful.
510

replaced the vss then unplugged the buffer waited 5 minutes then pulled the brake fuse and waited 5 minutes but no luck transmission still not shifting and no speedometer.

34 people found this helpful.
825

check the ignition switch harness for power drops across the white wire and the pink wire... it is a know problem for the harness to lose power there and causes loss of transmission shifting along with instrument cluster failures.

82 people found this helpful.
480

My 2000 Tahoe LT 4×4 has that not changing gears issue. Put it in drive - nothing, go to 1stthe and it grabs, you manually shift it, works great, even drops down gears and then changes great. The main problem is after I manually shift it, I come to a COMPLETE stop, it goes right into basically neutral, but if I don't COMPLETELY stop it keeps pulling. Once that happens, I have to manually shift it out again. Does anyone have an idea of what themayis be? issue

48 people found this helpful.
1,440

its more then likely the seo ign 10 amp fuse in the fusebox next to driver door the fuse looses power causing instrument panel failure and transmission goes into a nuetral state

51 people found this helpful.
920

You said check the ignition switch harness for voltage drops I think that could be my problem because when I check the buffer voltage I only get five volts at the speedo buffer I thought I was supposed to have at least 12 volts is that correct? Do I possibly have a bad ignition switch ?

65 people found this helpful.
1,170

I just replaced my trans in 01 Yukon. I'm having the exact problem originally stated by dfrinzi. speedo not working and won't shift out of 1st in od but I can manually shift from first to second but not 3rd or fourth. Jw if this problem was resolved and how to go about it thanks.

99 people found this helpful.
1,440

Speedo sensor in transfer case I replaced it now it shifts fine speedometer works like it should and I haven't had any other problems

29 people found this helpful.
250

I had similar problem and mine turned out to be the safety neutral switch.

25 people found this helpful.
1,440

I retract my last statement worked good for almost 2 weeks then started acting up again I'm at a loss

24 people found this helpful.
410

I found a TCM fuse (10) under the hood that was blown. Was hard to tell for certain but I replaced it and the speedometer and transmission are working properly now

41 people found this helpful.
400

I have a 2005 Tahoe and my speedometer and gas gage doesn't work gas gage stays buried over full and speedometer stays at zero any ideas?

40 people found this helpful.
1,170

Speed sensors on the top side of transfer case, one or the other is bad or unplugged

18 people found this helpful.
880

I have no power to the 10 amp Trans fuse. What color wire at the in essence which supplies the power to that wire? 95 gm 1500 4x4

39 people found this helpful.
440

just replaced the trans cooler lines due to a leak and now my 02 trailblazer wont shift and speedo not working all the time

44 people found this helpful.
920

I replaced my ignition switch and problem was solved I wasn't getting 12 volts to the speedo buffer behind glove box

27 people found this helpful.
210

I've got no speedo and had 2,3,4 but no 1st. Took it to tranny guy who scanned it and cleared codes, now only 1, and 2 manually like it's in limp mode. My vss is good, ignition good, but my tccm is corroded. Could that be the whole problem. 2001 s10 zr2

21 people found this helpful.
490

I am having same problem 99 tahoe abs light comes on speedometer not working could it be my ignition switch harness?

49 people found this helpful.
210

I'll try the ground behind engine passenger side in wire harness thanks Desmon Cross the man I say...

21 people found this helpful.
260

Hello everyone , i goth a gmc sierra 1996 4x4 with 75 000 km. I have a problem about my gear when i shifted with it. When i put the gear on (regular) the trunk going in front like the gear (Drive)... If i put the gear in (reverse) i goth nothing... If i push some gas when im in (reverse) the motor sounds like overload .. Do you think is the cable ? Or the tranny ? Or a sensor ? Or the neutral switch ?

13 people found this helpful.
1,710

It "AIN'T" the speed sensor. PERIOD!!!!!..... It "might" be in the circuit that comes from the speed sensor or one of the parallel or series circuits that the speed sensor is also interconnected with..... But in more than 95 percent of the cases that have been brought up in any of these forums thus far, replacing the speed sensor "DID NOT" solve the issue..... I'd be willing to bet that anyone who encounters this problem will find the solution only through tracing ground connections within the harness..... Codes thrown in one instance where it says that the speed sensor or one of the temp sensors, or the IAC, or the map sensor is the cause, will only pop a different code for another sensor when you replace the one that shows bad..... There is either a bad ground or a short to ground somewhere in the wiring harness..... Good luck finding it, cause in most vehicles where all the sensors are connected to the ECM or PCM, all the sensors are interconnected within the ECM, and are directly influenced by the feedback from another sensor...... Some of you have just been lucky in finding a solution by merely replacing the "one" sensor that isn't grounded right or that is shorted somewhere in the harness. If I ever discover the specific short or bad ground in the circuits on my 94 GMC 1500, I'll let you know where and what. Till then I'm seriously considering selling this thing for scrap and getting a ford.

33 people found this helpful.
160

Please do because mine is acting up. My speedo started going haywire but I'm not sure if it's a loose wire because it happens and then it stops. One day it will be fine and one day it won't be. I could hit a pothole and it starts to slip out of gear. I'm going to go to the scrap yard and get a couple used vehicle speed sensors and try it for the helll of it

12 people found this helpful.
1,710

I got in touch with GMC about getting a tech manual, or whatever else I could use to chase down the problem on my truck......They didn't have anything on before 96, but the lady I was having the chat with sent me a couple email addresses.....One was....... http://www.autobooksbishko.com/search.cgi?year=1993&make=GMC&category=Shop+Manual.....The other was Helms, but I just randomly selected to go with bishko.....Cost $44.67 to get a cd on "my" 94 sierra, plus of course the various options that it could have come with in the same line.....It has cost me around $70.00 in ink to print out all the pages I've wanted to look over better.......Hard to bounce around the PDF file as quick as you can a book, especially when you have to flip back and forth every once in awhile.....The printed manuals themselves cost a bit more than the cd.....But if you wanted "every single of the manual" printed out it would probably cost you about three times what the printed manual itself cost's.......Personally I'm glad I went with the cd.......At least that way if a page gets destroyed by the wind of saturated in oil, I can easily print out a new one.....from either the original disk, the backup I put on my hard drive, or the one I put on a small flash drive......I have about 800 pages out of over 3000 printed and it told me "exactly" where to look and what to test to find at least "one" ground wire disconnected that literally killed my battery while it was running. Oh.....Update.....I decided 'before' receiving the cd to replace the distributor because I discovered an oil slick inside of it, and clear evidence of dried oil like stains on the plate......actually caused by a deformed and cracked distributor gasket.....I just decided that, "If I'm gonna take it out and have to put it back in right, then I'm going with a new one".....At least 90 percent of my problems were cured with the new distributor, but there was/is still a little glitch.....start right up, stubborn about idling till it warmed up good, run like a new one, almost is all new now.....After it gets hot, if you shut it off, it ain't starting back up......Took a 60 mile round trip, left the engine running when I stopped by a couple stores and a friends house for maybe fifteen minutes each with the doors locked.....Set and idled like it was new, ran great though the speedometer didn't work at all, and I later discovered that neither did the rear lights.....The manual literally told me exactly what to do to find the broken ground wire beneath my truck, and where it was located......I was hoping that "that" was the problem....But no........I have come to the conclusion, whether correct or erroneous, that my starter solenoid is half shot, 'but' in order to find out, you have to, on my truck, take the starter off the truck just to get to the blame terminals to do the test's that the manual describes...IF IT WAS A FORD, I could tell you in five minutes if the solenoid was bad......But I will have to say that the GMC has been generally much easier to work on otherwise.....I'll let you know tomorrow evening whether or not it "was" the solenoid that caused the last of the problems. Though I may just decide to go with a new starter....Either way, I'll say something even if it's just "damn!"

6 people found this helpful.
1,710

for what it's worth.....Finding the loose ground wire, and reconnecting it where it was supposed to be "at least" fixed the speedometer....I ain't saying that that is "your" problem with the speedo, just that fixing the broken ground fixed my speedometer problem.......

19 people found this helpful.
300

i had the same problem on my 98 chevy pu with a 4l60-e transmission,gages stopped working speedo reads 0 and abs lite came on .....took it to my transmission shop they looked at it took 10 min to find problem....the wires going to the vss sensor had been chewed up by a Squirrel....spliced wires back together and problem is fixed...all is working fine.

30 people found this helpful.
70

I got a 1995 chevy k1500 5.7ltr 4L60E tranny and mine did same thing i replaced output on transfercase cleared it right up..

7 people found this helpful.
110

Had all the same problems. Even had tranny rebuilt and still same issue. Replaced everything only to find at the last that the ignition switch inside steering column was the problem. Found it on amazon for $52.00 Works great now!

11 people found this helpful.
120

I have an 05 Tahoe Z71 my problem is the speedo pegs out all the time. Sometimes I show no oil pressure, tach will peg out. Fuel battery and temp are always good.

2 people found this helpful.
120

also sometimes if I go back and forth several time on the ignition but not turn it over it will reset the panel for a while.

10 people found this helpful.
80

I'm haveing the EXACT same problem that Raymond commented up top some. I don't see it being my transmission considering I have every gear. Please any input helping me would be appreciated!! Thanks My 2000 Tahoe LT 4×4 has that not changing gears issue. Put it in drive - nothing, go to 1stthe and it grabs, you manually shift it, works great, even drops down gears and then changes great. The main problem is after I manually shift it, I come to a COMPLETE stop, it goes right into basically neutral, but if I don't COMPLETELY stop it keeps pulling. Once that happens, I have to manually shift it out again. Does anyone have an idea of what the issue may be?

8 people found this helpful.
1,710

Z71Doug. I am very far from being a mechanic. However, from some of the research I've done because of my own problem with a 94 GMC. It "sounds like" you might have a problem either with trash in your trans fluid blocking or partially blocking one of the fluid chambers. Or with one of the solenoids acting up inside the transmission which will prevent it from changing gears properly. But, like I said, I am far from being an experienced mechanic, and can only hypothesize.

8 people found this helpful.
350

I have a 2001 Yukon 4X4 that wont shift into 3rd or 4th. My speedometer doesn't work, the ABS light is on and showing a P0502 DTC (circuit low). Need some input on this issue.

32 people found this helpful.
1,710

For what it might be worth, the first thing I'd try is to look for a short somewhere in the speedometer circuit, the ABS circuit, or the instrument cluster to ground circuit. May possibly even be a fuse, gauges fuse, brake fuse. But like I said above. I ain't a mechanic I "think" that an electrical problem can effect the voltage that should be going to the 3-4 shift solenoid and "maybe" stop it from shifting right. Go to an auto parts store and buy either a Haynes manual, or a Chiltons manual for the Yukon. Might help you some. And hope a "real" mechanic gets up in here and gives you some good advice.

7 people found this helpful.
110

We just went trough the exact same thing, 99 sierra z71 with np246. U joint took out the adapter housing, changed it, put transfer case in and tranny wont get out of 2nd gear and would only get to 2nd by manually shifting it. We did ohm test on wires from sensors and they all read 4.5 except one, from the speed sensor on right PASSENGER rear tailshaft of transfer case. The wire coming in read 17.5 and had stretched I guess during the removal process...wire fixed and all lights went off and shifts normal again. If your checking your ABS on front sensors, jack the wheel up spin it and it should read .350 coming out of the sensor at plug...just in case you have a bad wheel sensor and we eliminated that. If anyone takes a transfer case out I suggest unplugging all wires to dropping it due to the fact that the wires are too short to let transfer case sit on the ground. Cant tell you how relieved we are and I wanted to update this post to try and help. I also posted a picture of the adapter plate to help anyone contemplating changing out a cracked adapter. I will post our install and uninstall also. Going to share my experience after uninstalling 4 np246 NP8 transfer cases and installing 3 this weekend on sons 1999 sierra 4x4. There are not that many videos out there so some helped but passing this info on, last uninstall and install took 1.5 hours total. IMPORTANT, LOOK AT NUTS AND ENSURE YOU ARE DROPPING JUST THE TRANSFER CASE AND NOT THE ADAPTER HOUSING ALSO. There is no need to loosen adapter housing unless it is cracked as ours was, if adapter is cracked that requires crossmember drop and tranny jack to hold transmission up because adapter housing sits on motor mount and bolts to transmission, change rubber O ring on front of adapter is all...no gasket required. If you need a new adapter apparently GM has an updated strengthened housing There is no need to drop crossmember, case has no mount because it just hangs on back of adapter housing attached to transmission mount. Considering the adapter lasted 17 years with 75 pound transfer case hanging off of it is impressive. I like the design for install lol. Tools needed 11 mm box end for u joint saddles 15 mm small 3" box end, 1/4" ratchet with 15mm socket 18 for drain plug, 19 for sensors Oil transfer hand pump zip tie Uninstall 1. Take off both drive shafts this makes getting to nuts so much easier and you do not fight trying to stab the front shaft while trying to stab 6 studs through adapter, might as well replace u joints if they have movement if none just shoot em with grease. 2. Drain case, drain plug 18mm 3. Loosen 5 of the 6 15mm nuts holding transfer case on studs. The small 1/4 ratchet is a dream for 5 top and side nuts, box end for bottom nut but leave bottom nut tight until wiring is unplugged because trapped oil in adapter will run out. 4. Unplug all 3 sensors and other 2 plugs. 5. Loosen last nut and let oil drain in pan 6. Slide case back, kick tail shaft up, turn case at an angle and it will clear the crossmember. A second person for this is the ticket, if your solo like I was for one of the installs it is tricky but after resting case on chest it worked out. Install 1. Ensure all sensors and new seals are in replacement unit, if used unit...finding correct seal for front shaft is pain so keep your old one so you can check O.D. AND I.D. . Oreillys number, 710495 2. Make sure flange on adapter is clean and all oil is out of inside of adapter 3. Lift case and work it around until the tailshaft and studs are above crossmembers so that you can rest them on both crossmembers. 4. Now put gasket on the studs as your buddy lifts the front of case a little allowing you to do so. 5. Stab case ensuring the gasket is still in place 6. One person can hold tailshaft while other puts 2 nuts on to hold it in place, now relax and reverse steps 1 thru 6 above. Note, our fill plug was stuck so instead of cracking case attempting to break plug loose we just took off sensor on right side of tailshaft and filled through that hole with hand pump. Hope this saves at least one person a headache.

11 people found this helpful.
25

I have a 2001 Chevy Blazer 2WD 4.3L SFI 6cyl. Just like the original poster, my speedometer is always at zero. Unlike the original poster, I have no issues with gear shifting; it goes from 1 to 4 with no problem. My odometer is also frozen at the same mileage. Any ideas as to where I should look first?

2 people found this helpful.
100

The wire is going to the transfer case there's three plugs all the plugs are the same the plug that goes to the transmission harness make sure your color codes are all the same I just done mine speedometer will not work got them looking the probe was hooked up backwards truck does a good job now transmission works perfect speedometer works perfect

10 people found this helpful.
60

I have a 2003 Silverado that I just replaced the 5.3 motor on i drove it home from work and it ran great no issues the next day I went to drive it to work and once it warmed up it stopped shifting almost like the tranny went out but I have had no issues with it I had to call a tow truck and when he arrived he drove it up the flat bed with out a problem once I got to work the mechanic there checked it out but we can't figure out what the problem is it drives fine until it warms up any ideas what it could be?

6 people found this helpful.
10

i Have to replace my Shift Solenoid (1-2) any idea if i have to drop the pan 2005 Z71 Sierra 5.3L

1 people found this helpful.
350

Yes you have to drain and drop the pan. Your trans is a 4L60E.

3 people found this helpful.
160

i had the same problem with no speedometer and no 3rd or 4th gear shift. it was a wire connection behind the battery that came undone. i plugged it back in and everything worked. it came unplugged when i took out the battery. thanks

12 people found this helpful.
160

it was a plug that came undone when i took out the battery. thanks.everything works just fine now.

4 people found this helpful.
80

Wires pins on plug to speed sensor were pushed in to far on plug not sticking out far enough to make contact. Pulled back out with needle nose and gently plugged back in. Problem solved

8 people found this helpful.
80

I recently purchased a 02' Chevy Silverado w/4WD. Everything running great until returning from an out of state trip. Within 10 miles from home the speedometer began jumping all over the place, later when slowing down to turn at an intersection the speedometer dropped to zero and would not shift out of 1st. After 1st checking fuses, I replaced both speed sensors located on either side of transfer case. Truck works great now, cost less than $70 for two speed sensors, used a 3/4 box end wrench on one side the other required a 3/4 deep socket.

8 people found this helpful.
100

I have a 2004 gmc sierra 1500. Speedometer doesn't work, transmission works fine

10 people found this helpful.
100

I just had work done on my 2000 Silverado z71 transfer case and now I got a abs light and break light and only has 1st and 2nd gear this only happend after the transfer case replacement I've replaced all the sensors on the transfer case check vacuum lines I don't know what else to do?

6 people found this helpful.
110

had same problem I checked with multi meter on hertz for signal coming off vss (on driver side rear of trans. I had signal there , so I tested same two wires at ecu and had no signal. I traced wires from vss purple with white stripe and light green with black stripe and found the purple wire with white stripe was broken where small harness joined large harness which is on top of trans. had to undo all plugs and remove driveshaft to pull harness over for repairs

4 people found this helpful.
60

My 1996 Chev Silverado 4WD. The Speedometer and tach stopped working, and the auto trans wouldn't shift out of 2nd. Checked all the fuses, then the ignition switch connections. Found the problem when I removed all 5 connectors to the computer, under the hood on the drivers side, and put them back on. The tach, speedometer and transmission work fine now.

6 people found this helpful.
20

switched out trans on 01 Silverado , now my indicator lights are very dim and no speedometer and wont shift out of first gear . help

2 people found this helpful.
60

I had a similar problem after repairing my transfer case due to the pump rub. Wouldn't pick up speed until about 30 mph. Harsh shifting if it did. AND and brake lights on. After checking just about everything, it turned out to be the aftermarket tail housing that didn't have a counter bore for the o ring seal for the speed sensors. Even with the o ring removed the sensor but would not seat flush to the transfer case when tightened. The sensor in the old housing bottomed out at hand tight. The sensors in the new housing would only bottom out when torqued to about 40 ft lbs. Once I torqued them properly every thing worked.

6 people found this helpful.
50

I had replaced my Actuator motor and rebuilt everything in my transfer case all new parts had no speedometer no shift found Actuator motor is the issue the brand new one something in it was making it not wire upright I had no power at the center for the speed sensor so I changed it back to the old one just plugged it in to the wires and tested for power lo-and-behold powers back so when you buy a new Actuator motor all you guys make sure you stop power at your speed sensors when you replace it you should have 5 volts to 6 volts or more if you do not the new actuator is most likely bad or wrong

5 people found this helpful.
60

Hey GM enthusiests just a note for the transmissions issues, I found out the hard way and extensive research, the electronics are different in different years of transmissions, example 93-94 year 4L60e trans has a twelve pin trans plug,95-98 has a 13 pin trans plug as GM added a solenoid to the trans for shift control and 99 and up are different still the earlier ones used analog signals up until OBD 2 control systems were introduced around 95. a 95 4L60 e trans will look almost exactly like a 94 except for the extra pin and it won't communicate with the trans module

6 people found this helpful.
90

Have a 2001 Chev Silverado K1500 4x4. Brake light and ABS light come on and other times they stay off. With just the ABS light on truck still moves as it should. When the brake light comes on the speedometer stops working (goes back to or remains at zero) and it will no longer shift out of first gear. I'm loosing my marbles over this, someone please point me in the right direction!!!

9 people found this helpful.
20

check your fluid gm engineers a safety lockout in the event of low fluid or pressure

2 people found this helpful.
60

08 GMC savana 3500 (one of many in a fleet)- truck had problems with speed sensor wouldn t go over 10mph, shift out of first and would just rev. Replaced the speed sensor and worked fine. About a week later problem started up again. mechanic said it needed a new trans. Let the truck sit for about 2 months... started right up it run for about 10 minutes and driver it around the block. Worked great (without doing anything) about 10 more minutes into driving it the problem started happening again. Won’t shift out of first, check engine, abs, and brake light all popped up. Any ideas? Thanks

4 people found this helpful.
60

Wanted to also add- truck runs fine when it’s cold. Once it warms up all these issues start happening. I also saw the “D” on the shifter blinking.

2 people found this helpful.
20

I have a 97 5.7 4x4 tahoe. Had a salvage yard 99 transmission rebuilt with deep pan to replace my cracked case with a shallow pan. We did not figure that one out for a few days. Put all back together ran for about 10 miles perfect shifting. It threw a couple code....like the solenoid b and the p0740 torque converter shift circuit/open. We finally got fluid level correct from shallow to deep pan. As of right now... the tahoe will go in all gears sitting, it shifted at first perfect and then started with no od, then no od or third, now it no od, no third, and second rpms go up to 3500 before shifting and it only shifts when i let off gas. The abs brake light is on also. This tahoe ran perfect until i cracked the case somehow, now i have been trouble shooting for over two weeks and getting nowhere and very anoided with this and not haveing wheels. Ive read so many with same issues but speedometer not work also, mine works but the abs light is on now, and my dash light for park nutural and drive is not lit. I was told that its the speed sensor on transfer case. I will try that tomorrow. If anyone has any ideas....im game to try it! Thanks

2 people found this helpful.
20

2002 GMC Sierra 5.3. Gauges flicker and transmission starts shudder shifting between gears. 1 to 2 & 2 to 3. 4th seems to engage fine. It happens when the engine and transmission are at operating temperature (Hot). When I unplug the 4 pin plug on the top of the alternator, the transmission & gauge cluster seem to work fine, but I am not charging the battery. Must be an electrical issue somewhere? Very puzzling. Its been doing this off and on for over a year. I have taken it to two shops and it will not do it when its there. They even looked for voltage drop across the wiring. I have been throwing parts at it hoping to come across the sensor or issue that may be causing this. I have cleaned and reassembled all the ground locations I can find, cleaned all harness plugs I can reach, looked at all the fuses and have had the dash apart twice. I even ordered new ground stripes and added them in various locations. I have replaced: ALTERNATOR, BATTERY, FUSIBLE LINK, MASS AIRFLOW SENSOR, THROTTLE POSITION SENSOR, MAP SENSOR, BOTH TRANSMISSION SPEED SENSORS, IGNITION SWITCH, IGNITION KEY CYLINDER, NEW ECM FLASHED TO MY TRUCK, REBUILT GAUGE CLUSTER. The issue persists.

2 people found this helpful.
10

Same thing happened with my GMC Yukon 1999 went to the mechanic the problem was just a fuse. Hope this helps

1 people found this helpful.
40

I have a 2000 Silverado 4x4 with a 5.3. I replaced the rear main seal because I had a steady drip.. when I put it all back together the truck will not shift out of 1st gear. I can manually shift to 2nd but ,if I go to 3rd it will drop back to 1st. and also my speed ometer isn't working. im getting 12 volts to my sensors. I have park, reverse, 1st & 2nd. 4 lo and high works fine. been messing with it for 4 weeks now.. any one have an idea???

4 people found this helpful.
60

1998 GMC 2500 4x4 5.7L 4 speed auto. My speedometer dropped to zero then trans wouldn't shift correctly and ABS light came on. I replaced the input and out put transmission speed sensors. That fixed all issues described. Hope that helps someone else.

6 people found this helpful.
80

i have a 2001 gmc sierra that i replaced the transmission on and now it only has first gear and speedometer doesnt work now. I changed out both shift solenoids, checked the vss, and replaced neutral switch but still doesn't shift out of first and speedo doesn't work. Don't know what else to do.

8 people found this helpful.
20

I have a 1996 Chevy Silverado 2500 four wheel drive 350 speedometer won't work and won't go in reverse it just sits there won't back up any answers to what causes that

2 people found this helpful.
10

It’s one of the plug ends going to the speed sensors what you need to do is get you a ohms reader that has where you can check DC current unplug the plug ends and check one side should have around 0.640 and the other side 0.040 I would almost bet money that’s what’s going on I replaced the transmission in mine and the speedometer wasn’t working and wouldn’t go past second gear what happens is the wiring harness is a little short and you pull the wire loose in the plug end you can go to any auto parts store and get a new plug end and wire it back in and your good to go hope this helps

1 people found this helpful.
50

Actually it's going to be harder to replace that plug then to just take a pic and unplug the plug from the sensor and use the pick to pull the little prong back out what happens is prongs tension getsweak and doesn't make a good connection so if you pull it out again it will pressed tightly and we'll fix the problem do that on all three connections on your harness to your sensors and add some dielectric grease before you plug them in and it should fix it the last guy was correct on the problem just not on the easy way to fix it if you cut the harness and try to put a new plug on that you're going to have to solder and heat shrink it if you just pull the prong it's going to have more tention than the new plug will and will work better than a new plug good luck

10

I had the same problem, I changed my radiator out and had the same issues. 1998 GMC k1500 speed gauge stuck at zero and trans wouldn’t shift unless you done it manually and then only first and second gear. Changed out my speed sensor at the back of the transmission and fixed it all. I have only put 10 miles on it, but I will update if it starts up again.

1 people found this helpful.
20

Changed the transmission 01 5.3 suburban speedometer at 0 doesn't shift and abs light,is on. Switched around the three plugs as much as I could thinking,that I might have put a plug on the wrong sensor , no luck. Ive got two plugs that have purple wires and one plug that has a green wire. Not sure where they go. Ive switched out both sensors on back of the transfer case , unhooked the battery with every new combination and I still have no luck . has any one got any ideas?

2 people found this helpful.

I have a 1994 Chevrolet Blazer “Silverado” trim package (full size 1/2 ton truck style not S10 blazer) that had same issue: no read on speedometer usually and wouldn’t shift thru the gears on its own (sometimes would randomly read speed and shift fine). Replaced vehicle speed sensor and plug at back of trans with no change. Looked over wiring to sensor and found a spot in harness up near trans bell housing that wire for speed sensor had bared itself out a little allowing it to ground out periodically and kill the reading from sensor. Repaired wire and has worked fine since and this was about 3 years ago. Now I have started having having blips of the speedo going away at random over some bumps and have had the ECM-IGN fuse blow causing truck to die as that kills signal to fuel pump as well (not power to pump just signal for it to turn on). I’ve found that the insulation for the wiring to the speed sensor had deteriorated from fluid exposure near original repair which is what most likely caused first ground out issue. I had to replace a section of both the green and the purple wires to get rid of exposed wiring and cure the speedo issue this time. Can anyone shed light on if it’s possible that the sensor wires shorting to each other could cause the ECM-IGN fuse to blow?

50

Got the same issue replaced vss on transfer case checked all fuses replaced grounds and ignition switch same issue any other ideas out there

1 people found this helpful.
20

loose 2 wire connector near battery cause, reconnected runs great, ck first, it looked connected but was not

2 people found this helpful.
50

Hey gregg can you send a pic of the wire

4 people found this helpful.
10

I have a 1996 Chevy Silverado ck1500 that has 1st,2nd and reverse.the speedometer and maybe gas gauge Dosent work. I have replaced the shift solenoids and got new transmission fluid and it still won't shift into 3rd. Any help would be appreciated

1 people found this helpful.
10

I have a 1988 Chevy 2500 with 5.7 l and 700R4 transmission. The guage cluster brake light would flash like in a code. 1 long flash and and 8 short flashes. Then the speedometer would quit working and it would immediately drop out of overdrive. And then the service engine soon light would come on. When I used a jumper wire to read the code,it showed code 24. VSS error. Open circuit or no activity. After I tested wires for continuity and different things, it ended up being that I replaced the gauge cluster. The VSS speed sensor buffer 88 to 91 models is in the motherboard in the gauge cluster. It's been two weeks and the truck is running just fine.

1 people found this helpful.
40

This may help many of you- I have a 2004 Suburban K1500 LT 4x4 5.3l gas L60E. I had no speedometer function, both ABS and Brake light came on whenever I drove it a minute or two (and it chimed for EXACTLY 33 times every time that happened, every time I re-started the vehicle!), CEL also illuminated. Vehicle would not shift out of 2nd gear either. Replaced both (yes, there are TWO speed sensors - same item #, they are located at the 10 and 2 clock positions on rear end of Transfer Case - at driveshaft end). After searching interweb and youtube etc for hours, I came across a video that suggested checking all connections of wiring harness on top of and around Xmisssion and Transfer Case. I found a damaged wire - looked like a mouse or something had feasted on it. It was kind of a pain since it was right on top of the TC- connected to a speed sensor from inside wire loom! Spliced it back up and - viola! Speedo works fine, shifting is perfect, ABS/Brake/CEL lights off now (after code reader used to clear codes). So I'd suggest checking all wiring on/around Xmission/TC, including plugs/connectors etc. ESPECIALLY any wiring that is not inside a plastic split wire loom protector - such as wires that are exposed or simply some have tape around them - like a single twisted pair of wires, or single wire. Eventually they will end up inside a loom, BUT the issue is with those sections outside the loom and the protection it provides- they're less protected so more vulnerable (mice/rodents appear to like wire insulation more than plastic loom material). Note: don't be afraid to tug and pull a bit - that's how i found my damage. It "looked" ok but when I tugged on it, the wires separated and I saw the damage to them. Unless I had tugged and pulled a bit, I'd still be scratching my head. Hope this helps!. <

4 people found this helpful.

Your Answer:

Sierra 1500

Looking for a Used Sierra 1500 in your area?

CarGurus has 26,465 nationwide Sierra 1500 listings starting at $1,990.

ZIP:

Own this car?

Share your experience with others.

1999 GMC Sierra 1500

Review another car

CarGurus Experts

  • #1
    dragonflyoffshore
    Reputation
    10,380
  • #2
    yetilikesbeer
    Reputation
    10,320
  • #3
    John Saffrahn
    Reputation
    10,080
View All

Know more, shop wisely

Search

Related Models For Sale

Used Chevrolet Silverado 1500
3,997 Great Deals out of 79,784 listings starting at $2,295
Used Ford F-150
5,167 Great Deals out of 97,676 listings starting at $1,300
Used Toyota Tundra
1,233 Great Deals out of 18,473 listings starting at $4,450
Used Chevrolet Silverado 2500HD
1,075 Great Deals out of 23,594 listings starting at $3,050
Used Dodge RAM 1500
199 Great Deals out of 3,085 listings starting at $1,999
Used Toyota Tacoma
1,421 Great Deals out of 29,406 listings starting at $4,270
Used GMC Yukon
788 Great Deals out of 11,767 listings starting at $2,500
Used Ford F-250 Super Duty
1,430 Great Deals out of 22,002 listings starting at $2,552
Used Chevrolet Tahoe
1,488 Great Deals out of 21,381 listings starting at $2,400
Used Chevrolet Camaro
746 Great Deals out of 12,734 listings starting at $4,950

Used Cars for Sale

2022 GMC Sierra 1500 For Sale
3 Great Deals out of 4,039 listings starting at $32,670
2021 GMC Sierra 1500 For Sale
235 Great Deals out of 3,514 listings starting at $32,075
2020 GMC Sierra 1500 For Sale
192 Great Deals out of 3,078 listings starting at $26,000
2019 GMC Sierra 1500 For Sale
180 Great Deals out of 2,857 listings starting at $19,988
2018 GMC Sierra 1500 For Sale
210 Great Deals out of 2,798 listings starting at $15,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.