hey guys,

I gotta friend of mine who will sell me 3:73 gears for my truck. I have 91 F-150 2WD with the 8.8 rear axle. I currently have 3:08 (top end gears) in my truck right now, will this swap work. Please say yes tks for the help guys

91

 

This is exactly what I am looking info on, can't seem to get any responses. One guy on the forums here has swapped the 8.8's. I think most people put in the 9 inch instead of swapping gears in the 8.8

 

Don't really have any info on a 91' I have a 2001 Scab that had 8.8 and 3:08 that I changed out to 3:73. From what I've found out, it appears that Ford doesn't make 3:73 gears for the 8.8 but other mfg's do. So I guess you would have to research pt #'s. If the gears are used, you should becareful, make sure you get an installation kit for the proper mfg.,new bearings and shims and stuff like that. imho the change is worth the work involved.

 

Ford offered 4 different rear ends for the F-series, 8.8,9.0. Dana, 10.25 (f100-F350). Did your friend say what rear end the 3.73's came out of? If they came out of an 8.8 you shouldn't have any problem. Summit carries Ford Racing 3.73 gears for the 8.8 for $190.

 

My 1994 Ranger has a 8.8" with 3.73 gears. Axle gear splines on Ranger are 28 spline! Ford sells 3.73 r/p for 8.8".

If You wish to go from 3.08 to 3.73, everything should changeover. watch out for 31 spl. (F-150) and 28-spl. (Ranger).