2001 4wd


Asked by Feb 15, 2012 at 09:32 AM about the 2001 Chevrolet Suburban LT 1500 4WD

Question type: Maintenance & Repair

I have a 2001 Suburban with 140K miles. Just recently it stopped shifting into 4wd. When I press any 4wd mode, the switch just blinks. I can hear the motor on the middle transfer case engage. Is there a way to test the actuator? It seems like the switches on the dash are doing their job, and the transfer case motor is also. Would like to confirm actuator is bad. There are no check engine lights on, or service 4wd lights on. Thanks!

1 Answer

Eric Fritz

I've had a similar issue with my 01 burb, first off let's go over how the whole system works. The switches on the dash send a signal to the control module that then actuates either the encoder motor on the Tcase (the one that engages the clutches and shifts the range gear, on the front/bottom of the Tcase), it also sends a signal to the actuator on the front differential (on the front/top of the diff, about the size of a pop can) to engage the pinion gear to the axle shafts. If one of these motors fail, the other will still work, but no power will be transmitted to the wheels because the system is not fully engaged. A good home diagnostic test is to see if the front is trying to lock in by turning the vehicle to run, but don't start it. Then have helper press 4hi while you listen under the vehicle to see which one is working, and which one isn't, both should attempt to shift at this time. Since there is no service 4x4 light on, I would guess that your front actuator failed, but be sure to fully diagnose the situation before you go throwing parts at it because a front actuator is $150 and an encoder is $250 :( If you really want to be sure (this is what I'd do) First change the front diff and Tcase fluid (80w90 up front, synthetic Dex6 ATF in the Tcase, 2 quarts or so each) then, if that doesn't help, take the front driveshaft out (mark it's orientation on the front yoke) and shift into 4x4 with the engine off in run mode, now grab the front yoke and try to twist it, if it's locked into the wheels, it engages, now shift out of 4x4 to see if it disengages. Next, try to twist the driveshaft on the Tcase, it will be very hard to turn even if it is disengaged because the clutches always drag, see if it locks to where you can't turn it when the 4x4 is engaged, then you'll know if the encoder works or not. MAKE SURE THE VEHICLE IS IN PARK WITH THE WHEELS BLOCKED! Hopefully this will help you troubleshoot the problem. Good Luck!

3 out of 3 people think this is helpful.

Your Answer

Add photo

Related Questions

  • Transmission question 1 answer

    Can I put a 4 l65e transmission in a 2001 Suburban

    2001 Chevrolet Suburban 1500 4WD


    Maintenance & Repair

  • 4WD Gears 1 answer

    Recently bought a 1994 "4WD" 1500 Suburban with a 5.7 engine. Found out the 4WD electrical cable was disconnected underneath sub so I connected it and then discovered the front wheels are not moving ...

    1994 Chevrolet Suburban K1500 4WD


    Maintenance & Repair

  • Why does my 2001 chevy surburban k1500 4x4 goes from drive to neutral 1 answer

    I have a 2001 Chevy surburban k1500 4x4 that goes from drive to neutral! I tried replacing the neutral safety switch but it still does the same thing.tried using a code reader but nothing comes up! ...

    2001 Chevrolet Suburban 1500 4WD


    Maintenance & Repair

  • 2001 chevy suburban service engine soon light 1 answer

    I have a 2001 Chevy Suburban. When I drive 70 or over the service engine soon light flashes. In the same drive it flashed 13 times and went off for about 2 to 3 minutes then flashed 49 times and pau...

    2001 Chevrolet Suburban LT 1500 4WD


    Maintenance & Repair

  • engaging 4wd in 1991 v1500 2 answers

    Hi I have a 1991 4wd suburban. Is there anything special about engaging the 4wd? I have had a friend tell me that i need to be stopped, have the tranny in neutral and then shift into 4wd - then switch...

    1991 Chevrolet Suburban V1500 4WD



Search Chevrolet Suburban Questions

Chevrolet Suburban Experts

#1 Eric Fritz
Eric Fritz
Reputation 800
#1 Andrew Olsen
Andrew Olsen
Reputation 800
#3 Neal Turner
Neal Turner
Reputation 700
View All

Related Models For Sale

Used Chevrolet Tahoe"
1,040 Great Deals out of 36,534 listings starting at $1,695
Used GMC Yukon XL"
223 Great Deals out of 6,739 listings starting at $2,495
Used GMC Yukon XL Denali"
199 Great Deals out of 7,529 listings starting at $3,986
Used Ford Expedition"
585 Great Deals out of 21,300 listings starting at $2,111
Used GMC Yukon"
547 Great Deals out of 14,667 listings starting at $1,500
Used Cadillac Escalade"
376 Great Deals out of 11,172 listings starting at $2,999
Used Chevrolet Silverado 1500"
2,381 Great Deals out of 143,344 listings starting at $1,195
Used GMC Yukon Denali"
30 Great Deals out of 4,627 listings starting at $6,900
Used Lincoln Navigator"
147 Great Deals out of 6,064 listings starting at $1,999
Used Ford F-150"
3,170 Great Deals out of 215,803 listings starting at $1,000
Used Toyota Sequoia"
170 Great Deals out of 6,664 listings starting at $2,977
Used Chevrolet Silverado 2500HD"
388 Great Deals out of 33,935 listings starting at $2,998
Used Ford Excursion"
12 Great Deals out of 872 listings starting at $3,500

Used Cars For Sale

2017 Chevrolet Suburban LT 1500 4WD For Sale
352 listings starting at $55,421
2016 Chevrolet Suburban LT 1500 4WD For Sale
14 Great Deals out of 3,157 listings starting at $35,389
2015 Chevrolet Suburban LT 1500 4WD For Sale
79 Great Deals out of 1,449 listings starting at $29,900
2014 Chevrolet Suburban LT 1500 4WD For Sale
7 Great Deals out of 149 listings starting at $26,900
2013 Chevrolet Suburban LT 1500 4WD For Sale
22 Great Deals out of 384 listings starting at $15,998