What's different about it?

 

Porsche put they're name on it. How else do you think ExxonMobil grossed 36 billion in profits last year?

 

it has different additives that allow a greater load carrying ability and shock resistance as well as the correct lubricity for synchro engagement.

 

Do you have a data sheet for that mobil gear oil?

 

http://www.mobil.com/USA-English/Lub...90_80W-140.asp

AKA Mobil Delvac Gear Lube...name was cahnged to align it with other mobil delvac product lines...

 

THAT WAS MY POINT!

Pay the cash, get the deal.


There is zero relevance between oil quality and brand sponsorship. Grow the hell up girls!

 

UPDATE: I've driven the car for about 300 miles now with Mobil1 LS 75w-90 in the diff/transmission. I HATE IT!!! I had minor problems with a bad second gear synchro before the change over, but now I've got what I'd call serious problems with the second gear synchro and problems with the 3rd gear synchro.

My one caveat was that I was only able to put in about 2400mL of fluid, at this point the fluid level was up to the drain plug. I thought I read that capacity was 2750mL and that the level should be about 5mm below the drain plug. Anyone know for sure???

 

 

FormerGMguy, I use 2+ Liter of gear oil but don't keep track of exactly how much. I have the car on 4 jackstands so the car is level. I always fill it to the top to the point where it start to pour out. Its hard to drain every bit of oil out of the trans. Try redline, it may reduce your synchro problems. Mobil 1 felt too slick for the synchros to function properly in my opinion. When I took the tranny apart, the "felt" material on the face of the synchros is what spins the gear to "synchronized" speed. I believe there needs to be a certain amount of "friction" or surface tension of the oil for proper operation. Its my understanding of how synchros work from looking at it while its apart but I could be way off. I just know redline worked best for me and I buy them by the cases of 12.

 

Aren't there two plugs; an upper fill plug and a lower drain plug? Which one did you fill to?

 

That pretty much sums up what I've read since putting the Mobil1 in. Do you use the MT90 or MTL?

Oh, and I filled to the top drain plug. I suppose I should have called it the fill plug rather than the "drain" plug.

 

If you got worn syncros a slicker oil will make them worse. There job is to make the gears speeds match for proper engagment.

 

I have run both. I don't like either. I have the MT 90 in now and seems to be just as notchy as before. But I think that is just the nature of the beast. My tranny shifts fine except when it is realy cold and second gear is a bit of a bugger to get it in. The MT 90 seems better with the cold weather than the Mobil 1 I had in there earlier. Good luck and report back.

 

Very interesting that you are having shifting problems with it.
Definately file that one away for future reference. 2400mL sounds close. No idea where 2750mL is from, but I've never fit more than 2200mL or 2300mL into a 944 transaxle.

I will be switching to MTL probably next week, I will be sure to let you guys know how it acts.