I have a 2003 F150 xl sport 4.6 5 speed. Anyone know what Diffs I have? I know their open and the front in a 8.8. Is there a standard on the 150's for the spline count? I'm assuming my rear diff is a 8.8 aswell then?

Thanks,

Will

 

just look at the shape of the diff - oval = 8.8, pear = 9.75

 

well the rear is a pair so i have a 9.75 in the rear and a 8.8 in the front? I know i have a 3.55 rear gear ratio. Any guess on the spline count?

Thanks,

Will

 

Spline count for axles or pinion ? I think the axle spline count is 31 but not absolutely sure, or is it 34 ?

 

Alright thanks man, the spine count was for the axles, I want to get a LSD and drop it in after moving over the ring and keeping the stock pinion. I like the 3.55 gearing for the most part. I'll check with ford but my local dealer isn't too eager to help me out...


Thanks again,

Will

 

Always thought the 5.4s came with the 9.75 while the 4.6s had the 8.8?

 

9.75 has 12 bolts on the cover .... 8.8 has 10 bolts

your door sticker will tell you the gear ratio and LSD or non-LSD

there is also a coded tag on the pumpkin

 

nope, 5.4's can have the 8.8 as well