Thumbs up to F150online forums - lots of good information being shared. Can I swap my '04 F150 FX4 9.75 RG / 3.55 with an '04 F350 rearend? Need to know if this swap can be done. If so, please share your experience / cost or point me in the right direction. I was told it could be done, but I cannot find any info on this topic. Just replaced my rearend ($2100) because my axle sheared off. I have a slidein camper permanently welded to my frame (removed my bed) and I am a little bit on the heavy side. Decided I would like a 1T rearend instead of my 1/2T.

 

Can it be done: Yes. Absolutely.

Is it a bolt in? No idea.

You need to measure the overall width, the spring perch width and make certain that the pinion is in the same space between the tires as the F150. You are going to have 2 different bolt patterns unless you go with aftermarket axles.

If you are not worried about the bolt pattern issue and if the overall width is not too bad, the possibilities include:

Moving spring perches
Adapting the brake lines/cables
Possibly changing the U-Joint to match up with the new yoke.

If you sheared an axle with the load, it is probably too heavy for your chassis.
Good luck. Be Safe.