rear main seal oil leak and tire pressures

[Tazio Nuvolari]

My 2002 996 Turbo {just over 50 M 6-speed} developed what appears to be a rear main seal oil leak. The coincidence is very eerie. Oil used is the Mobil 1 European blend. Anyone having had a similar experience ? Has anyone ever used a sealant type of oil additive ? Any success or failure ? Am trying to avoid the costly repair. Tire pressures. Am using 35# front and 37# rear yielding pretty even wear. Tires are
Michelin sport p's.Fronts are holding 7/32" and rears are 4/32" with both after circa 10 M miles of my possession. Your input is appreciated. Bring it on.

[Tom]

Not a 996, but same results here. Before my rebuild, my 951 motor would not drip a single drop of 10-40 dino oil (Castrol GTX). When I tried Mobil 1, it started leaking in multiple places, including the rear main. I switched back to a 'high mile' dino oil and the leaks stopped. That said, on a 50k mile 996 Turbo motor, I don't think I'd mess with additives or the like....

[aboyandhisdog]

Pretty sure that for an M96 engine of this year a rear main drip wouldn't be unusual. But for the turbo engine that you have I just don't know for sure. I do think that some of the additives for a rear main will work. I used it once (I think the Bars Leak brand) in an old Willys engine with some success. Follow the directions closely and don't overuse it. You want the seals "plumped up", not disintegrated.

My 997 calls for 36psi front, 42psi rears. I like a higher pressure as our roads stink and I don't want a bent rim. So, at 42 front and 48 rear, I find they wear more evenly and I've not damaged them from hitting a hole.

[Central+996]

I use Driven DTS in my 996 with 125k and seldom let the revs go under 3k. This cured my slight main seal drip in a month or so. Mobil1 seems to have a thinness issue in older vehicles.

[spanner]

I used Mobil One at first, but after I did the IMS and main seal install, main seal twice...ugh!.....I began to use Driven and never looked back. As for using some sealing magic, it may work for old Detroit irons, but for this motor, I would avoid and bite the bullet and drop the motor.....while you are there.....budget for perhaps a clutch, main seal, and flywheel as well....
There is nothing that can be done on the cheap to any 996 Porsche engine, but at least it doesn't have all the nanny idiocy.