I recently bought a bargain 97 F150 4x4 with a bad rear-end - axle code 19 (3.55 gears, 3800 lb, Non limited slip, [8.8 i think]). I've never had a 4x4 before, and don't want to make any assumptions. will a 3.55 limited slip be interchangeable? how about a 3.55 out of a 2wd? Also, what years are interchangeable?
I'd feel alot better if I could find a schematic in-case I have to swap around gears or something. the schematic I found in another post is different (newer and a 9 inch i believe).
I'd appreciate any info anyone can give me!

(my '94 needs a break after 240,000 hard working miles!)

 

Yes 19 is a 3.55 open diff. H9 is a 3.55 factory limited slip and I would think that the differentials would be interchangeable as they are also both 8.8. I believe that the 97-03 model years are very close between the 9.75s and the 8.8s repsectively but you would have to verify the spline counts. Im pretty sure that my H9 is a 31 spline but you NEED to check ur diff tag. Use search there is a gob of info on it

 

Thanks for the info parnAZ! I can't check the diff tag - thats how I got the bargain... someone swapped rearends (with the wrong one) and sold it to the guy I got it from - and apparently removed the tag (not that it would help me)! It pulled itself on the trailer with the front drive.... I'll try the H9 if I can find one cheap enough... Thanks again!

 

1997 through 2004 Heritage models will fit. If your 4x4 has a 4.2 V6 or a 4.6 V8 it has an 8.8 differential. If it has the 5.4 then you have a 9.75 differential.
Try http://car-part.com/ and fill in the blanks.