I recently started noticing a gooky sludge that reminds me of what antifreeze looks like in the oil of a car, in the radiator. Has anyone else had this problem? Is this leaking from the transmission oil cooler to the radiator. I checked, my transmission is at the full mark and does not show any signs of antifreeze getting into it.
I can not think of any way that oil from the crank case could get into the radiator and not get into the oil. The car is running fine and has not thrown any codes concerning the engine. My only code is with my ABS System saying it is not communicating. This is a problem I have been working on, but cold weather has stopped me from chasing it any further until things warm up.
Thank you for any advice on this issue with the radiator.
Oh, yea, I was also noticing that Autozone carries 2 versions of this car's radiator. One with a sensor and one without. Interestingly enough, the one with out the sensor hole costs more than the one with the sensor hole. Any, idea of which one I will need to order?
Oil in the Radiator?
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GregtheBear
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- 95naSTA
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Re: Oil in the Radiator?
No coolant on the oil dipstick?
The only place I can think of (outside of the unlikely head gasket failure) is the lower intake manifold gaskets failing between the coolant ports and the lifter valley. But that flow direction is pretty unlikely.
Are you sure it's not ATF? Maybe the radiator is leaking internally to the transmission cooler section.
The only place I can think of (outside of the unlikely head gasket failure) is the lower intake manifold gaskets failing between the coolant ports and the lifter valley. But that flow direction is pretty unlikely.
Are you sure it's not ATF? Maybe the radiator is leaking internally to the transmission cooler section.

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GregtheBear
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Re: Oil in the Radiator?
flushed the radiator system. Found the water pump had a small leak so replaced it. Also changed the thermostat just for kicks. Still not finding any water in the oil. Car is running ok and no gunk buildup yet. Maybe it was the issue of the GM antifreeze. I am running the old style antifreeze now.
- luke_dubs
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Re: Oil in the Radiator?
Sounds like you just had old Dexcool, and it started to deteriorate. Hopefully the radiator wasn't damaged internally.

'02 Pontiac Bonneville SE 108,539 miles, N/A, SSEi exhaust system, boat roller mount. Gone, but not forgotten.
'13 Buick Regal GS 122k miles, 270 hp, 295 lb/ft, ZZP intake.
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