Funny you should ask as I have spent the last two days working on my 98 T5 V70 with 160,000 miles trying to find the oil leak.

Recently had increased amount of oil leaking. First noticed after an oil change, oil all over the top of the motor. That was an easy one-just a bad filler cap gasket. But still had oil leaking on the ground. I posted here, was suggested it might be the oil separator box or plumbing being clogged, causing crankcase pressure, and blowing out the rear main seal.

I tried a bottle of Sta bil no leak (guaranteed to work) but that just made my car leak worse. It got to the point where I could not drive the car, it was leaking so badly. I shopped around for a indy shop to do the rear main, but the best price I could find was $1000. I had already purchased the oil separator kit from ipd, was $115 delivered. I decided to do the oil separator kit project myself and have the shop do the rear main. I used the instructions from Matthews site. I started the job yesterday. I did NOT have the tell tale smoke puffing from my dip stick tube.

I found no clogged tubing anywhere, and my pcv valve was not clogged either. I did find a lot of rotted vaccuum hoses, which I replaced.

Based upon what I have read recently, o0il leaks can be from the gasket on the filler cap being cracked or broken; or your front or rear cam seals can be leaking; or your rear main seal can be leaking. That's it.

As long as I had everything torn apart on the oil separator box project, I decided to check my rear cam seals. There was a lot of oil on the back side of my engine. I pulled off the cover plate on the exhaust cam, unscrewed the 10mm bolt and washer, and discovered my rear cam seal was just sitting there, not even seated in the block. I was very excited that I would not need a new main seal after all. I purchased volvo seals at the dealership for $11 each and replaced both the rear intake and exhaust seals. Easy job.

It took me two full days to get the car back together. I just got back from my test drive. The car runs like crap now, won't idle, no power braking assist either. I looked under the car and still have an oil leak from somewhere to boot! I'vd done something wrong in the reassembly or I broke something. I am going to give it another go tomorrow. On a positive note, I don't think I need to do my rear main seal anymore!