Go and order your rebuild kit and make sure it includes new syncronizer rings, tapered roller bearings, caged gear
bearings, and seals.
To rebuild the unit, lay out all your old and new parts.
First, clamp the main shaft in a soft jaw vice with the output end facing up. Put the reverse gear bearing on the
main shaft and then drop the reverse gear onto the main shaft.
Put your new reverse syncronize ring on the reverse gear.
Put the 5-reverse syncronizer body into the oven at 320 for 20 minutes.
Once its good and hot, grab it and drop it onto the main shaft making sure it seats all the way down towards reverse
Note that this syncronizer body must be installed with deeper hub facing down (toward the input side of main shaft).
Go ahead and start heating up the rear mainshaft tapered roller bearing.
Reinstall the large snap ring to ensure the 5-reverse syncronizer body can't move on the shaft.
Install the syncronizer sliding ring and the detents and springs onto the 5-reverse syncronizer body.
Put the new 5th gear syncronizer ring onto the 5-reverse syncronizer body making sure the teeth line up in the sliding
Install the 5th gear roller bearings onto the main shaft.
Drop 5th gear onto the shaft and then grab the hot tapered bearing out of the oven and drop it onto the mainshaft.
Tap it down to make sure its seated.
Once the bearing is cool, reinstall the snap ring you removed during dissassembly.
Flip the mainshaft over in the vice so the input end is pointing up. Get your new 1st gear roller bearing and put it
on the mainshaft. Then put first gear on the mainshaft.
Get the new 1st gear syncronizer ring and put it on the taper of first gear as shown.
Heat up the 1-2 synronizer body and drop it onto the main shaft.
Reinstall the large snap ring to ensure the 1-2 syncronizer body can't move on the mainshaft.
Next install the 1-2 syncronizer sliding ring and the three detents and springs onto the 1-2 syncronizer body.
Remember the tapered face goes towards 1st gear!
Get the new second gear roller bearing and install it on the mainshaft as well as second gear.
Next, put the 3rd gear bearing race/spacer and thrust washer in the oven to heat. Once they are hot, drop them on the
mainshaft after second gear. Tap down to make sure both are seated.
Once these have cooled, install the new 3rd gear bearing and third gear.
Put the new 3rd gear syncronizer ring onto 3rd gear taper.
Heat up the 3-4 syncronizer body and drop it onto the mainshaft next.
Reinstall the snap ring to hold the 3-4 syncronizer body onto the main shaft.
Inspec the input pocket bearing race and oil scoop in the back of the input shaft for damage. A new oil scoop ring
came with my rebuild kit but mine was in good shape so I didn't replace.
Heat the input shaft pocket bearing in the oven and drop it onto the main shaft.
Main shaft is now rebuilt.
No pictures, but heat up the two tapered roller bearings that go on the countershaft and drop them on.
Now install all the bearing races into the front and rear case halves. Do not install the bearing shims under the
races in the front case half at this time!
Mesh the mainshaft and countershaft together and bind them up with a ratchet strap.
Set up the mainshaft and countershaft such that the end is hanging off your workbench. Then slide the rear case half
over the main and countershafts.
Carefully grab it all and stand it up.
Make sure and space the case up a bit as the mainshaft output extends slightly past the end of the case.
Grab your new reverse idler gear shaft bearings and install them along with the reverse gear idle shaft and reverse
gear idler bearing.
Take the front case half and slide it down over the main and countershaft.
Put some bolts in to hold the case halves together and then flip the works over.
Now we check the bearing clearance to determine the shims we need to set the proper bearing preload. Tapered bearing
preload is very important with this transmission since the case material (aluminum) is different from the main and
countershaft material(steel). These two materials will expand at different rates when in use and hot and this could
lead to excessive clearance in the tapered roller bearings.
To check the mainshaft tapered roller bearing clearance, set up the dial indicator on the output end of the mainshaft.
Pry up on the end of the input shaft. Make note of the clearance.
To check the bearing clearance on the countershaft, I used a magnetic level on the 4th gear driven gear on the
countershaft and set up the dial indicator to measure off of it.
Then pry up on the 4th gear driven gear of the countershaft from the other pto hole in the front case half. Note the
clearance from the dial indicator.
Once you have these clearances with no shims installed you can calculate the required shim thickness. For the
countershaft you take the clearance and add between 0.00079"-0.00434" to this number and that is the required shim
thickness you need to add under the front race on the countershaft tapered bearing. For the main shaft, you take the
recorded clearance and subtract the thickness of the new oil baffle. Then add 0.00079"-0.00434" to this number and
you have the required thickness of the main shaft front tapered bearing shim. I was lucky and the shims I removed
from the transmission would work to set proper preload after rebuilding.
Turn the transmission back over and remove the front case half. Set up your blind bearing race puller and slide
Pull the two bearing races from the front case half and then install the shims and hammer the races back in the front
You will have to pull the main and countershafts out of the rear case half to install the shift rails and collars. It
will be a pain to get it all back in the rear case half but it can be done with no special tools.
Reinstall the socket head screws to the shift rail plate in the rear case half.
Reinstall the reverse idler gear and shaft. Install the lower bolt through the case to hold the idler shaft in place.
Don't forget the magnet.
Install the main shift rail.
Pick up some anaerobic sealant from the parts store and lay out a nice bead on the flange of the rear case half.