RADIATOR LEAKING SOMEWHERE?

10

Asked by Nov 29, 2014 at 09:09 AM about the 1995 GMC Sierra 1500 C1500 SL Standard Cab SB

Question type: Maintenance & Repair

I HAVE  95 SIERRA 5.7 V8 WITH 240K MILES AND THE RADIATOR DRAINS
EXTREMELY FAST BUT THE FLUID IS NOT DRAINING VISIBLY. I HAVE CHECKED
MY OIL AND IT IS OT DRAINING INTO THE MOTOR, I RECENTLY CHANGED MY
WATER PUMP AND THERMOSTAT BECAUSE OF OVERHEATING, BU NOW I CANT
FIND THIS LEAK. ANY SUGGESTIONS ON WHERE TO LOOK NEXT?

7 Answers

One way you can try is with one of these. They can be rented, pumps air in to radiator, do it cold, engine off. Fill radiator then pressurize and see if you can find leak

2 out of 2 people think this is helpful.
11,010

could be an intake manifold gasket.

8,650

Look around the thermostat. Some thermostats are under the engine and the leakage is hard to see. Did you fix the overheat problem?

10

I believe so. After replacing the thermo the truck didn't overheat until this morning about a week after replacing. I'll try the pressure tester this afternoon

10

Ok update. I can smell antifreeze through my vents very strong when I turn on my heater and there is a small leak coming from the heater box on my firewall. I guess the next step will be to check that out

1 out of 1 people think this is helpful.
11,010

you have a bad heater core.

2 out of 2 people think this is helpful.

With that additional information I agree with mikepriestlake. Text-Book symptoms. If/when you do the pressure test make sure heater core has coolant flow to it. i.e turn it on first, run for a few minutes, allow to cool (does not have to be stone-cold just don't pop a hot radiator cap)

Your Answer

Add photo

Related Questions

Sierra 1500

Looking for a Used Sierra 1500 in your area?

CarGurus has 67,165 nationwide Sierra 1500 listings starting at $2,700.

ZIP:

Search GMC Sierra 1500 Questions

GMC Sierra 1500 Experts

#1 dragonflyoffshore
dragonflyoffshore
Reputation 4,930
#2 John Saffrahn
John Saffrahn
Reputation 3,490
#3 Glenn Clingenpeel
Glenn Clingenpeel
Reputation 3,070
View All

Related Models For Sale

Used Ford F-150
2,247 Great Deals out of 209,704 listings starting at $1,499
Used Dodge Ram 1500
448 Great Deals out of 11,375 listings starting at $700
Used Toyota Tacoma
502 Great Deals out of 39,894 listings starting at $1,995
Used GMC Yukon
349 Great Deals out of 17,287 listings starting at $2,500
Used Chevrolet Tahoe
576 Great Deals out of 27,581 listings starting at $1,500
Used Chevrolet Camaro
147 Great Deals out of 32,614 listings starting at $1,729
Used GMC Sierra 2500
163 listings starting at $5,900

Used Cars For Sale

2017 GMC Sierra 1500 For Sale
35 Great Deals out of 42,308 listings starting at $20,121
2016 GMC Sierra 1500 For Sale
85 Great Deals out of 3,801 listings starting at $18,977
2015 GMC Sierra 1500 For Sale
95 Great Deals out of 3,913 listings starting at $15,400
2014 GMC Sierra 1500 For Sale
103 Great Deals out of 4,309 listings starting at $14,495
2013 GMC Sierra 1500 For Sale
64 Great Deals out of 2,097 listings starting at $9,260