H9 Axle code - Both 8.8 and 9.75?
 

Hi Guys,

I just bought a 98 Expedition with a bad rear axle. The carrier bearings failed and it's pretty messed up.

The door axle code is H9. The tag on the axle identifies it as an 8.8" 3.55 ratio locking rear.

I've found a 2001 Expedition in a local PIY yard that also has the H9 axle code on the door sticker. However, the tag on the rear identifies it as a 9.75" 3.55 ratio locker.

If I pull the rear out of the 2001 I can get it for $100.

So, is there any reason I can't put a 9.75" rear in the truck? Any other parts I should get? Perhaps the driveshaft from the 2001?

Thanks.

Some answers to my own questions from searching.

There are 2 issues, one real and one potential.

Beginning in 2000 the wheel stud size increased to 14 mm from 12 mm. That provokes interference with the rotors and the wheels. I suppose I could put a set of axles from a pre 2000 9.75 in.

The other issue is driveshaft length. Apparently the 9.75 is about 1" longer than the 8.8. However, I've seen posts that say this is and isn't a problem. Anyone know?

It isn't going to be a good deal if it doesn't fit.

Yes, at this point I'm inclined to rebuild the 8.8. It's out of the truck and will be up on a bench in the garage later today.

I really don't want the hassles of having 12 mm studs on the front wheels and 14 mm studs on the rear.