I have a 2002 F150 4x4 4.6L with a 3.55 gear ratio and 8.8 ring size. I bought a new one yesterday and everything is the same except the new rear end has smaller lug nut studs than my old one. Everything on the new rear end says the same as the old one. It is a 3.55 & 8.8 but I am just wondering if the new one is for a 2X4 insted of 4x4 which may be the difference in the lug nut sizes. Hope I did not confuse anybody. Any help would be appreciated.

 

Hey 817johnn,
Ford used the smaller 12MM lug studs on the early F150's. After Ford had the lug nut recall they started using 14MM lug studs.

 

Correct. I believe from 97-99 they used the 12mm studs. 2000 on up, maybe even 99 on up they used 14mm.

You probably just bought an older rearend.