Im looking to lock up the rear but the dealership couldnt gave me the wrong information. 1st what size it the rear end. 8.8 or 9. what is the spline count on the axles. and what is the pinion diameter. Thanks

 

You need to tell us what you have first. What engine do you have?

 

I think that it is a 9.75. The nine is super easy to spot because the whole carrier loads in from the front.

http://www.fordracingparts.com/
Download the catalog (its big). On page 139 they have a limited slip for the 9.75. It says:

9.75" “TRUE TRAC”
LIMITED SLIP
DIFFERENTIAL
M-4204-TT31
• Torque-sensing differential
applies torque to wheel
with best traction
• Refined enough for
street use, stout enough
for rigorous off-road duty
• 34 spline count fits all 9.75" axles to 2006


Hope that helps.

 

Its a 2006 F150 XL V6 Manual 5 speed. Single Cab.

 

96F150 has a point. I basically told you what I have.

Can you snap a picture of it from the rear? We may be able to tell you better that way. Ford used to put the 8.8 with the smaller engines and the 9.75 with the bigger GVW ratings.

 

The V6 trucks have the ford 8.8 inch rear end. I think the 4.6 V8 trucks also use the same rear end.

 

Anybody know the spine count on the axles and the pinion diameter
thanks

 

31 splines, not sure about pinion diameter