Axle Ratio for Towing Question

Reply Subscribe

Thread Tools

Search this Thread

01-06-2013, 10:14 PM

#21

byoungblood

Senior Member

Join Date: Dec 2011

Posts: 418

Likes: 8

Received 32 Likes on 25 Posts

Quote:

Originally Posted by rus

The 7 lug heavy duty F150 is a 9.75 rear not 10.25.

TOTALLY WRONG.

I KNOW for a fact that the 7700 is a 10.25 rear. I own one that I bought brand new from the dealer. The lightning is 9.75.

I put new 4.56 gears in my truck and they are the 10.25/10.5 sterling rear series. Not a 9.75. I also put a brand new, straight from the dealer, 2010 superduty aluminum rear cover. They have a 10.50 rear and this cover will not fit the lightning or 9.75 rear. Check with any Ford dealership or try putting a 9.75 cover on any 7700 rearend. It won't even cover the pumpkin.

Those 7700 GVWR F150s were rebadged F250 "light duty" models. It was really a matter of carrying over the axle from the existing F250 model and was never used in the F150 again afterwards. I'm guessing it was decided that the 10.25 axle was overkill for a 1/2 ton truck when the frame and suspension weren't capable of utilizing the full capabilities of the axle.