The Stovebolt Site Forums The Shop Area Driveline 1949/1955 Rear trans. ident/retainer issue

Hi Guys:

Last week I was happily driving my truck when, boom! it got stuck, rear wheels locked. It took 14 guys to push it to the side of the street. Thought it was the gearbox, but thank goodness it was the differential.

A bearing broke. As I disassembled it, found out it had a metallic retainer. I don't seem to find one. Can I use a rubber (I don't know if they are rubber or plastic, please forgive my ignorance) one?

Also, what kind of rear transmission is it? Here are some photos of it and also the retainer. Rear Transmission.

The gear ratio is 3.90. Also on the photos you can see some stampings in the pumpkin and the gear. The truck is a 49, but has some 55 parts. It is no longer a torque tube. Is it a Spicer (because of the ratio). Or is from another vehicle?

Thanks for any enlightening on the subject.

Hy Chinito Quan, that differential looks like it came from a 55 -59 Chevy 1/2 ton truck. I didn't see in your pictures which part had failed, I have never seen any rubber or plastic parts in that differential. I'll have another look at your pictures, and if I have more to say I'll come back.

3B. There is no photo on the transmission that show the broken parts, since I took the photos after I dissmantled the differential. The retainer I pictured is the one that goes from the pumpkin to the shaft. It is metallic, but I'm having trouble finding it that way. Can I use a rubber one same size?

Thanks

Hy Chinto Quan, that "retainer" is actually the pinion shaft seal, some newer seals with the same dimensions may come with a thin layer of plastic sealer, or rubber on the outside surface to enhance the seal of the bore which the seal is installed into, those would be acceptable replacements of the factory seal. Were you able to replace the parts which broke?

3B: Luckily just a bearing broke, without damaging the gears. I will change the three bearings, just to be on the safe side. Regarding the seal, is it possible to find the seal exactly as the one photographed, all steel. I've looked around here and no steel seal.

Thanks for your help

Hy Chinito Quan, the number I come up with for the seal is National 6818. It is pretty well standard now for a new seal to have a thin coating of plastic sealer on its outer surface, over its metal casing, I hope you can find the seal. Chinito, that differential uses a crush sleeve between the pinion bearings, it is a one use item, so you will have to get a new one if you want your new bearings to last. The crush sleeve establishes the bearing preload when the pinion nut is torqued to specification. Seeing as you are going to reuse all your old parts you shouldn't have to worry about which shims to use, just use the ones that were in there to start with, hope that helps.