What lube do you use in your rear end? ;o)

[prostreetC-10]

Okay......jokesters welcome I guess!

Getting ready to drop the 3rd member into my 9" housing and was thinking about the gear oil and weight. I have quite a bit of left over Sta-lube that is rated at 80/90 GL-5 (whatever that means). It is a posi so I realize I will have to add a friction modifier. Is that the correct weight and does brand make THAT big of a difference?

[Longhorn Man]

I always recomend synthetic

[Stocker]

Synthetic here also.... doubt if brand matters, but for the record, I have Mobil 1 75W-90 in my Eaton diff. Have used RedLine 75W-90 in others, no problems.

[prostreetC-10]

I've been reading some interested stuff on the internet. I'm seeing where guys are actually NOT using a friction mod in used rear ends with older clutch packs. They are saying the friction mod can cause the clutches to slip even more. I do understand the need for it on DD and other applications to the rear end won't pop and click around corners. This is going in a car that will see about 2 mile trips at a time. I am not concerned about the clutches because it will get a spool if and when this one goes out. Car will also see a little 1/8th mile track time. This car is ONLY for testing my Holley carbs and is in no way a cruiser or entended for any real street use.