defiance

So I recently installed an 8.8 with 3.73s. Used 2 bottles of Valvoline Full synthetic 75W-140. Added Friction modifier, between the bottles, should have added that first, because some of it probably came out in the end.

(not sure how much friction modifier I ended up putting in because it came in a 7oz tube, so it was really a guesstimate)

So now after 300 miles of being quiet, my rear end is whining when I turn (at sorta slow speeds).

The rear end is new, less than 100 miles on it when I got it, and the gears were already installed from the factory.

So before I blame the gears or the clutch packs, I'm thinking maybe use some royal purple and exactly 4oz of friction modifier?

AzPete

Drain it, add the proper amount of friction modifier and your choice of rear end lube. That noise is typical of the clutches not having the proper amount of friction modifier from my experiences with Ford vans....

defiance

I use THIS stuff, the only thing I could find at the time, where can I find just a 4oz bottle of something like champion locally?

Derf00

is your car lowered? Did you check the pitch angle?

defiance

Suspension is all stock

AzPete

I would go to Ford and use their friction modifier......always worked great for me.

lawrencecar1

+1 and royal purple

defiance

update

Got the friction modifier from Ford. Added it to a bottle of Royal purple, mixed it up and pumped it in after draining the old grease. So far the noise is gone, I guess I will keep listening for another 300 miles.

I ended up using 2 bottles of RP, and I know it will take another half. Is it fine for me to drive with half a bottle missing for a few days?