Hello, this is my first post in this forum.
Oil suddenly came out on my coolant container (Brown milky substance).My car model is S40 2001. A mechanic told me that it could be oil cooler problem but we don't know where it is located.

Please help.

TIA.

 

Kick the mechanic in the face.Check your oil if its mixed with coolant as well as at this point you are looking at a blown head gasket or a shot turbo.Having the two mixed is never a good sign it has to be addressed as soon as possible.

 

You are looking at a bad head gasket. Get a mechanic that knows what he is talking about. The only oil cooler I have ever seen that could cause that is on vws where coolant flows through the oil filter housing but I have never heard or seen that occurring. Same goes for a bad turbo, the housing would have to crack internally for oil and coolant to mix, once again I have never seen or hear of this occurring. Do not drive your car unless you plan on replacing the whole engine. If you have oil in the coolant there is coolant in the oil even if you can't see it. As the car warms up the coolant system pressurizes to around 15psi with a leaking gasket the coolant will leak into the oil system. The coolant will destroy your rod/main bearings as well as the cam bearings. Milkshakes are never good, sorry.

 

I believe that there is a TNN for oil in coolant and I believe it involved the oil cooler or possibly the transmission oil cooler.

Oops, there it is...
TNN43-48-2005-12-20 Title: Coolant Contamination in Automatic Transmissions
The root cause for some automatic transmission failures is glycol contamination from the engine cooling system. Severe cases of contamination are easy to detect by a visual inspection: The transmission oil will have a milky appearance and there may be signs of oil in the coolant reservoir. Less severe cases are impossible to detect without doing a chemical analysis of the transmission oil. This slight contamination is easy to overlook and will result in a repeat transmission failure. A small leak from the cooling system into the transmission can cause driveability problems long before there are any visual signs of contamination.

 

Auto naut, good info. I was under the impression he was talking about an oil cooler, not the trans cooler....but yes radiators fail a lot. Is tnn the volvo equivalent of tsb (technical service bulletin)? Sorry to be off subject I'm just trying to figure out the volvo terms so I can be more accurate.

 

I believe TNN = TSB.