So I'm going to go ahead and change the gears in my 04 FX4. My questions are. What read end is in these and front end? Where is everyone going to get theirs and what brand gears?

Thanks guys.

 

What motor do u have? V6 and 4.6 have the 8.8 rear, 5.4s got the 9.75 rear. All have reverse cut 8.8 in front. Gears check www.diffsonly.com, www.eastcoastgearsupply.com, www.4wheelparts.com. Ive had good luck with motives and of course yukons are top notch.

 

What gears you have now and what size tires?

 

Sorry, I have a 5.4

 

Currently I believe I have 3:55's reason I thing that is I'm currently running 35x12.50's and the trucks picks up speed ok. Thinking of going to 4:11's or 4:56's. I'm leaning more to the 4:11's though since I wont be towing anything.

 

4.56 is what you want


4.88 if you tow

 

Next question I've come across. What spline count are our axles? 30 or 31

 

34.