I put this in other powertrain, but there is no ome there. I need a quick answer on this.

I need some info. I have a 06 STX with a 4.6. I am now running 3.55 NLS gears. What I need to know, is, what spline do I have? 28 or a 31? I'm pretty sure i have a 8.8 rear end. I'm wanting to put in some 4.10 LS diff and gears. And if i'm right, what brand should I go with?

Please let me now. Thanks.

 

I believe the rear 8.8's on the 150's are 31 spline

 

Yep, 31 splines on all 8.8 F150's. Ford Racing and Yukon make a good set of 4.10's.

 

yea you have 8.8 31 spline rear 28 spline front. go to randy's ring and pinion they will have everything you need and will help you out. great guys to deal with. i just did the job not long ago and i do recomend that you have a good differential or 4x4 shop do it. i ended up taking my axles out and bringing them to the shop. oh just a quick tid bit of info im not sure what size tires you have. but i am running 315-70-17's with 4.56 gearset and at 60 mph i am running 1950 rpms a bit high in my book but still pretty good on fuel economy. good luck.

 

I have a 2WD and running 275/60/17 tires. At 75 mph on the highway, i'm at 2150 RPM's. Thanks for the info.