C900 Drivetrain Replacement
Inner CV Drivers
There are a couple of ways to determine if your inner drivers need to be replaced.
The first sign is that you have a shake in the steering wheel as you accellerate.
If you feel this, then most likely one or both of the inner drivers are worn.
The second way is to go under the car and feel the axle and cup together.
Take one hand and hold the cup, then take the other hand and twist the axle.
There should be little to no play in a good inner cv joint.
If you have the axle out of the car, you can just use your fingers and feel the inside edges of the cup.
Worn cups will have indentations you can feel.
Before removing the inner drivers, you must drain the transmission fluid.
With older transmissions, there is a 3/8" square drive nut or a 12MM hex nut behind the oil drain plug.
With the newest C900 trannies there is no drain plug at all. To drain the fluid out of these trannies, you need to pull off the rear cover.
Be sure to buy another gasket before doing this!
The inner CV driver is the cup shaped piece that provides power to the axle.
It is attached to the transmission with 5 bolts on the driver's side and 6 bolts on the passenger side.
It is EXTREMELY important to replace only one inner driver at a time.
The shaft end of the driver is attached to/supports the differential of the gearbox.
If both inner drivers are removed at the same time, the differential will fall within the transmission and it will be impossible to recover without opening the rear of the transmission case.
Also...be sure that you remove the bolts from each driver equally.
By this, we mean to loosen each bolt a little bit at a time and move to the next so that the driver comes out of the gear box straight.
This keeps the differential in a position to make installing the new shaft easier.
Once you remove the joint, there will be some very thin spacers. These are very important in aligning the differential to the pinion bearing.
Do not lose them and make sure they stay on the correct side!
Each driver should have some very thin spacer rings that fit between the housing and transmission case.
Be sure these have been wiped clean and are lined up correctly when you begin tightening.
The holes only line up one way, so just spin them around until the holes line up.
Reattach the driver to the gearbox. Be careful that the spring doesn't fall out into the transmission case.
Tighten each housing bolt a little at a time to make sure the driver goes back on straight.
Do not over-tighten the bolts...check your manual for the correct torque.
DON'T FORGET TO RE-INSTALL THE SPEEDOMETER CABLE!