Oil in my radiator and is not the had gasket

If your sure the head gasket is ok and there is no smoke coming from the tailpipe there is a possibility that it is actually transmission fluid.

It was uncommon for the S70's radiators to fail like this, usually they just start leaking out the side tank crimp. The radiator also houses a cooler for the transmission. It the seals go bad or a crack transmission fluid can leak into the cooling system. If your transmission fluid is black or brown it will look like oil.

I highly recommend you take it to a shop A.S.A.P.

If it is transmission fluid there is a good chance there is coolant in the transmission and that is very very bad. A couple of ounces of coolant in the transmission will cause the transmission to fail in a relatively short amount of time.

Take it to a shop and specifically ask for a glycol test of the transmission fluid. This will measure any amount of glycol (coolant) in the fluid. If there is none then thank goodness.
If there is, the the source of the leak (most likely the radiator) will need to be fixed or replaced and the transmission fluid will need to be flushed.

If you have bon't have a shop you can trust or have a hard time finding someone to do the test the dealer is required to have the test kit. It is a required special tool (specifically for XC90's) and they will be knowledgeable about how to use it and diagnose the cause.

Now with that being said there are a lot of knowledgeable independent repair shops out there and I don't mean to suggest one over another. Just make sure you can trust who ever you choose.


Now all of this assumes you have an automatic transmission...


I hope this helps and good luck.

Cracked head or block, look down in cylinders