RADIATOR LEAKING SOMEWHERE?

10

Asked by ABR4545 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

4 people found this helpful.
30,465

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 people found this 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:

Sierra 1500

Looking for a Used Sierra 1500 in your area?

CarGurus has 8,304 nationwide Sierra 1500 listings starting at $5,500.

Postal Code:

CarGurus Experts

  • #1
    yetilikesbeer
    Reputation
    12,340
  • #2
    dragonflyoffshore
    Reputation
    11,490
  • #3
    John Saffrahn
    Reputation
    11,440
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Ford F-150
318 Great Deals out of 13,660 listings starting at $3,800
Used Toyota Tacoma
46 Great Deals out of 728 listings starting at $8,995
Used GMC Yukon
15 Great Deals out of 966 listings starting at $5,890
Used Dodge RAM 1500
93 listings starting at $8,999
Used Chevrolet Tahoe
12 Great Deals out of 847 listings starting at $9,980

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.