I am looking at upgrading my stock open differential in my F150 and for the 8.8" 31 spline it can have a 3/4" cross shaft and a 7/8" cross shaft.

How can I tell which one my truck has so I don't order the wrong part. It is a 94 F150 5.0 reg cab 5 speed with 308's open differential.

Thanks

 

F series Trucks 87 and later will have 7/8" cross shafts, 31 spline axles and have an ABS tone ring. Explorers will also have the same setup but Rangers will likely have 28 spline and 3/4" cross shaft.

 

What are you buying to upgrade it?

Are you buying something to modify your current differential, or are you buying a new differential like a limited slip or locker?

 

I am looking to upgrade to a powertrax no slip.

I had bought a used ltd slip carrier from an explorer to put in but decided against it because of the installation cost of setting the gears.

The powertrax says the carrier doesn't need to be removed to install the unit and can be done in the driveway in an hour or 2.

Any thoughts?