I have a 2008 F150 that I am going to be running 37" tires on, so I figure I had better change the gears. I know most people go with 4.88's when running 37's, but how is the driveability with them? Can you still do 65-70 on the interstate without a problem? Would 4.56's be better for mostly on road driving?

Also just to make sure, I need a 8.8 reverse for the front and 9.75 for the rear correct? And for a new diff cover, just look for a 9.75?

Thanks

 

get the 4:88s. I run at about 2600 rpm going around 75mph.

if you have a 5.4 you need 9.75 and 8.8 reverse for the front.

yes look for ford 9.75 covers.

I had good luck with these guy's.

www.accuautoparts.com

 

yep he pretty much said it all

 

With 37s your definitely going to want 4.88s.