75W90 or 75W140 ???

[BamaMan]

I'm about ready for the gear oil in my new 8.8 inch rear assembly. Looked in their local auto parts store at their synthetics and there are two weights. Which do I use in this application?

[SVOBart]

75w90 is what is specified.

[BamaMan]

Get Mobil One 75/90 synthetic. Get 3 quarts. Iirc it holds ~2.6 Qts.

Also if you're running the TractionLok diff, you need to add the stinky stuff The factory manual specifies: Fill the diff through the normal filler to where it flows out, install plug into hole. Then add the stinky stuff in through the vent hole in the axle shaft tube.

I'm not familiar with the vent hole in the axle shaft tube. I was going to put the lube in along with stinky stuff before putting the whole rearend in. While I have it resting on a couple of saw horses.

[Jim W]

Not to disagree with the experts, but Ford now recommends 75-140 synthetic gear lube for the rear end. That is all we use now, with excellent results. Also, I personally prefer Amsoil to Mobil 1.

Jim

[65ShelbyClone]

Also if you're running the TractionLok diff, you need to add the stinky stuff The factory manual specifies: Fill the diff through the normal filler to where it flows out, install plug into hole. Then add the stinky stuff in through the vent hole in the axle shaft tube.

Or if you're lazy like me, just put the friction modifier in the first quart of oil, shake it up, and then put that in the differential.

[schlot]

The stock 7.5 rearends all have traction lock right?

Wayne

http://svomustang.blogspot.com

[Gator]

Or if you're lazy like me, just put the friction modifier in the first quart of oil, shake it up, and then put that in the differential.

Im lazy like this guy

[DAVEZ84SVO]

Im lazy like this guy

DITO DITO!!

Dave

[BamaMan]

Get Mobil One 75/90 synthetic. Get 3 quarts. Iirc it holds ~2.6 Qts.

My maint. book says 2.5 pints. Is it pints or quarts? I guess I'll use the 75W140, I can't see how it could hurt anything. The parts store has Mobile 1 and Amsoil. What seems to be the most popular in the SVO crowd?

[schlot]

Do you buy the friction modifier from Ford or is there an aftermarket material you guys use instead?

Wayne

http://svomustang.blogspot.com

[Jim W]

We stick exclusively with the Ford Ford Friction Modifier.

In the past 6 months we have done at least 15 rear end gear jobs, mainly 8.8 but a few 7.5, using Amsoil with zero problems.

Jim

[under pressure]

You haven't been sleeping well! What's up with that? Rick

[tateg]

Damn new meds.

You too? And I thought I was the only one.