As you can see from my username I have a problem with a 78 ford f 150. Well actually I have a few. One, it is not even mine and I spent all day trying to fix it for my brother in law... The rear axle bearings are shot. I have worked on many trucks in my days so fixing it would be easy I thought...I ordered all the parts and none of them are right. Everything the parts store says should be it, is not it. So it is a 1978 F-150, 4x4 with a 400 and 4 speed. I cannot find the code online for the life of me. The tag on the differential reads as follows:
WDM BZ 8CE
3 50 9 390B

I can find every WDM code except one with a BZ after it. I thought this was a 9" with probably 3:50 gears. From the round shape of it I am thinking perhaps this is a dana 35??? It has 10 bolts, approx 10 5/8" wide. I am lost. Does this make a a huge difference from what is normally in a 78 or is this what is normal? Is a dana 35 and a 9" the same thing?

When I took it apart there was only 1 seal, a mechanic who just happen to be at the parts store said there should be 2, 1 inner, 1 outer? They gave me a sealed bearing which is not what came out of it. Does not seem like it all would seal up right..but then again I only have 1 seal of the 2 if there is actually 2. I have what would be the inner but it only had the outer in it when I took it apart. The mechanic said they would press on and I am a machinist by trade and it is well over the tolerance we use so I don't think it will. None of the numbers off the bearing races cross with anything that the parts guy can find. Also the retaining ring I took off is almost 4 times bigger than what came with the new bearings. The only part of these new bearings the does seem to fit is the outer dimension, that will go in easily I think. I am worried the new retaining ring will just snap if I tried to press it on because it is so tight.

I hope this is not in the wrong area and I am sure this has been covered a 1000 times here but I need help getting this thing back on the road asap. Any tips, advise, knowledge you can share will be greatly appreciated. If I can figure out what diff this actually is I just might be able to get some parts..lol

Thank you all

 

I had issues getting the right bearings and races when I did my wheel bearings. I ended up taking the old ones in, both bearings and races, and matching the numbers up. The right bearing came with the wrong race and had to get that separate. Mine is a F250, so the axle is probably not the same so I'm not sure on the procedure and number of seals. On my rear end, the axle tube and gear housing had no seal between. That's all I really remember about it. My brother actually did most of the work on the rear, cause I was laid up after I took it apart, so I don't really remember how it all went together well.

 

WDM-BZ Ford 9" non-locking 3.50 ratio 78 F-150 built last week of March 1978 (8CE)
This rear SHOULD have the tappered roller bearing with an integral seal. This bearing has a seal that is to the outside of the bearing and integral to it.
The other (earlier style) bearing is a sealed ball bearing. The seal on this axle is pressed into the axle housing on the inside of the bearing.
On the tappered bearing, the bearing is lubricated by oil from the differential so the seal is on the outside between the bearing and retainer.
On the ball bearing, it is packed with grease and sealed on both sides from the factory so it doesn't need any differential lube. Therefore the seal is on the inside between the bearing and the differential.
No rears have two seals. Its either/or not both.
Is it possible someone has changed the axles? The axles will interchange if you use the bearing the axle was made for. There is a slight difference in the OD of the axle shafts so the bearings will not interchange between axles.

 

Here are some pages from the Ford Master Parts Catalog. The first identifies the rear according to the code, that will tell you which parts list (88) to use. the next pages are the #88 parts list.
click on the .pdf link

 

Here's the third page of the parts list

 

This truck has had over 10 owners so who knows what has been changed from what to what. Thank you all very much for the help, I have hope that I can get some parts now.

 

Sounds like someone swapped in an 8.8". First pic is an 8.8 and the second one is a 9".

http://s800.photobucket.com/albums/yy289/phatjack1981/?action=view&current=9inchford.jpg#!oZZ2QQcurrentZ Zhttp%3A%2F%2Fs800.photobucket.com%2Falbums%2Fyy28 9%2Fphatjack1981%2F%3Faction%3Dview%26current%3D88 .jpg%26

http://s800.photobucket.com/albums/yy289/phatjack1981/?action=view&current=9inchford.jpg#!oZZ1QQcurrentZ Zhttp%3A%2F%2Fs800.photobucket.com%2Falbums%2Fyy28 9%2Fphatjack1981%2F%3Faction%3Dview%26current%3D9i nchford.jpg%26

 

It is a 9" that much is sure, has no access plate on the back, everything comes out the front. Going to the parts store here in a few minutes, hopefully they can find what I need today.

Thanks again all for the help.