Rogue_Ant

Guys, I've got a 968 trans, and my 3rd gear synchro is a little weak.
Sorry to bring the oil discussion up, but since I'm not as familiar with the 968 stuff, and trying to search yields 1000s of threads...

What is the general consensus for a good oil to use?

Thanks.

JDS968

Mobil Delvac 75W-90 (previously marketed as Mobilube SHC). Not the same as the regular Mobil 1 75W-90 they have in AdvanceAutoZone.

Rogue_Ant

Thanks!
Any other opinions out there?

JDS968

There are other opinions out there, but they're wrong.



Sorry, I couldn't resist...

savvas944

correct ,opinions are like a rear body part,everyone has one.

Torsen is gear driven LSD,so Heavy MINERAL delvac may not be efficient
for normal motorway use.

If disc LSD,MINERAL oil GL6, with 2% lsd additive,either 75-90 or85-140
according to climate would be better.

if it is a dedicated track car without an external oil cooler,a heavy
synthetic or semithinthetic oil 75-140w such as REDLINE ,is fine
or 1 quart heavy/2 quarts lightweight shockproof REDLINE is even better
for endurance events.No affiliation with Redline at all.
Just experience with 50 brands of oils over 35 years of use.

For cooler climate 75-90 is fine ,but again a full synthetic is best.

mobil 1,i agree is aging quickly,and does not last the changes interval,deteriorates
quickly with overheating,marginal performance.

Rogue_Ant

Not a dedicated track car - closer to a DD than anything, and will rarely see any track events...

JDS968

Mobil Delvac 75W-90 is PAO-base synthetic.

Mobil Delvac Synthetic Gear Oil 75W-90, 80W-140.

I use it with my Quaife [Torsen-type].

fortysixandtwo

From the 968WSM

Capacity: approx. 2,75 l
Oil quantity:
Hypoid transmission oil SAE 75 W 90 to API GL5 or MIL-L 2105 B


There is no mention of a different oil type for open or torque bias differentials.

Rogue_Ant

How is it for street driving?

JDS968

The oil or the Quaife?

I love the diff, it's great on the street and on the track. No trouble or anything, just hooks up great in pretty much all conditions. Lots of fun in the wet

Rogue_Ant

The oil - I'm mostly concerned with synchro engagement - since my third-gear is a little bit more sluggish to engage then the other gears...

JDS968

Oh, sorry. In that case, I'm the wrong guy to ask. I've put so many track miles on my car, the synchros are ****. I'm convinced that if I opened up my transaxle right now, I'd find the 4th gear synchro entirely ground down to the point of non-engagement.

I just know I'm going to be rebuilding this damn thing sooner or later, but I'm dreading it. Anybody have experience with straight-cut gears in a 968 box?

Rogue_Ant

Hmm, ok thanks.
Anyone else have opinions?

Rogue_Ant

Come on people - 134 views and only two opinions?
Some of you have to have experiences to share...

JDS968

Told you so

Some people use Swepco and Redline. Porsche uses Mobil Delvac in their factory-backed racing efforts. Your box isn't going to explode much faster with either one of those.