Output Shaft Seal

[jimshoen]

Has anyone replaced the output shaft seal on the Allison Tranny? What tools do I need? How big a job is this?
Thanks

[Jon Wehrenberg]

For sure you will have to drop the driveshaft. From that point it sounds like an Allison question.

[lonesome george]

Replaced the output shaft seal in ours last winter, it is not difficult, here is a review of the job. Take this with a grain of salt, it is from memory.

Remove the rubber skit and the two plastic covers from behind the transmission.

Remove the driveshaft, I left the driveshaft connected to the differential, it will rest in the safety hoop.

Remove the output shaft yoke, two M8 cap screws with a lock tab, slide the yoke off the output shaft.

Remove the output seal, I used a cotter pin tool to get behind the seal and pulled it out.

Install the new seal, did this with a plastic hammer but you can almost push it in by hand, be careful not to get the seal too deep in the bore it has no shoulder to stop the seal from going past the face of the transmission case.

Allison sells a kit to reseal the output yoke, couple of O rings and new fasteners.

Take a good look at the sensor just in front of output shaft seal in the side of the transmission case, that one can leak too. It has a sheet metal cover over it.

I don't believe a lot of oil will leak out when the output yoke is removed but I'm not sure of that, mine was drained prior to the seal replacement.

Here are the part numbers for the stuff I used.
Seal #CA 29546238 $51.20
Yoke seal kit #CA 29535910 $20.03

Jim, give me a call if you want to chat about this. 317-539-5472.

[dale farley]

Jim, If you decided to replace your seal, please post us some pictures of the process.