I have two F-150's, one is a 2000 Reg Cab 4x4, 5.4 with the 9.75 rear end and 3.55 LS. I will be selling this truck soon. My new truck is a 2001 Screw 4X4, 4.6 with 3.55 Non LS . I'm kind of disappointed that my new truck has an open rear end. So, I'm considering swapping the entire rear end before selling the Reg Cab. It seems like there would be no problems with this. I would think everything should just bolt up. Is there something that would cause a problem that I'm not thinking of?

 

Well, I have tried to find out as much about this topic as possible, but there is not much info out there about swapping the 8.8 for the 9.75. As far as I can tell, everything looks like it should be pretty straight forward. I took some measurments and it should just bolt up, with no problems. The existing driveshafts in both vehicles shouldn't need to be changed either.

My only real concern is the ABS system or other computer related issues. Any info anybody can give will be helpful.

 

same gears so speed should be fine, use the same tire. check the u-joint size and drive shaft length. shocks mount same place?
good luck
randy

 

Shocks mount a little bit differently on the truck itself, but the mounting brackets on the rear end are the same. I didn't check the u-joint size though. Didn't think about that. Drive shafts shouldn't be a problem.

 

Just make sure the drive shafts follow the differtential. The 8.8 shaft is longer than the 9.75. I swapped a 9.75 for my 8.8 and I had to shorten the drive shaft. Everything else was a direct bolt up. The breather tube on the differential serves as a joint for the brake lines. It must be removed from the axle and left hanging. If you also remove the calipers and hang them you will not need to bleed the brakes as you never opened up the brake lines. The 9.75 is a lot heavier than the 8.8 so be ready for that. Oh, and don't forget to keep the rear disks with the corresponding callipers. They have worn themselves in to the brake pads. This will save you from having to turn the disks if you don't.

JMC

 

Thank You JMC. It's good to hear from somebody who has already done this. Everything you said is what I expected or had already planned on doing. It's just good to have those things confimed before I did the swap. Thanks.