i have a 97 catera i bought it a few months ago for my son. about a month ago i noticed a brownish substance in the water so i thought it might be the tranny fluid leaking over in the radiator ,so i put on an external tranny cooler but this did not fix the problem.it looks like it could be engine oil but it is not on the dipstick and is not mixing in with the oil and i have not noticed any use of oil any ideas what this could be ?????? thanks jim

 

Well if it still has DEX-COOL antifreeze/coolant (like all GMs use from factory)still in it, that could be just old fluid. But if the block is cast iron on those cars it could also be a lil of rust coloring from the cooling passages. I am not sure if they were aluminum or Cast but that should start you off in a good direction.

 

Also when oil mixes with water in an engine it tends to become milky so if it is that then you could probably just try some stop leak in the engine, then coolant flush it then see if it occurs again.

 

when was the cooling system serviced?
i suggest you jump over to our FAQ section and read a little,

then do the service, do not flush with chemical flushes - do NOT.
do the 50/50 refill and then, lets see what happens.

for all we know, all is fine, but not knowing when the cooling system
was serviced, not good. this a weak point on our cars, a very weak point.

come back and update ...




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