I just run whatever cheapest synthetic 75w-140 I can find.

 

No additive?

 

Mobil 1 75w-140. I've probably been running it in my car since 1997ish. No additives.

I've never rebuilt my T-lok. Still original clutches and putting down two stripes

 

Conventional 75w140 with a bottle of additive.

 

See: FCSD Chemicals and Lubricants And FCSD Chemicals and Lubricants (friction modifier)

 

Royal Purple 75w90 Max-Gear Lube and Ford Friction Modifier.

 

Valvoline 75w-90 gear oil with Ford Friction Modifier.

 

I use Mobil 1 75w90 but not because of any kind of magical oil voodoo... it literally just is the least smelly gear oil I've found 😁

No additive needed, it's inherently compatible with limited slip according to the bottle and my experience matches that (no chattering,etc)

 

I use Mobil 1 75w90 but not because of any kind of magical oil voodoo... it literally just is the least smelly gear oil I've found 😁

No additive needed, it's inherently compatible with limited slip according to the bottle and my experience matches that (no chattering,etc)

Interesting... All I have ever smelled had a terrible sulfur-ish smell

 

I run schaffer 75/90 only because it was free in a 5 gallon bucket.

 

I understood the general rule of thumb to be that synthetics don't need the friction modifier. The regular oil takes the friction modifier only if your worried about occasional chatter from the trac lock going around corners.

 

Anybody used the new flexfill pouch quarts of Valvoline gear oil? Can get those into tight spaces between mufflers and drive shafts or between the diff cover and the gas tank where the quart bottles can't. Why didn't I think of this?? Lol

https://www.summitracing.com/parts/vlv-889785?seid=srese1&gclid=CjwKCAiA7vWcBhBUEiwAXieItkaM4kY-1-9UGH2BlTfvTaRKj8Bu8YROLBjs1auJ0BOkweeIszARwBoCpX4QAvD_BwE

 

I bought a cheapy transfer pump from AutoZone.... Screws on top of the quart bottle and works pretty well... My ham fists still don't fit to squeeze the pouches...