Output Shaft and Coupler Spline Wear
Many units have severe output shaft and coupler spline wear in the tranny and transfer case. If this is the case with your unit, we sell the OEM 18 and 25 spline shafts or the hardened 300M version. We are also able to order new couplers for the t-case.
If the output shaft is worn, the t-case coupler is too and also has to be replaced! If it is not the coupler will chew up the new output shaft in short time as the saw-tooth wear on the coupler splines will round off the new output shaft splines and stress them intil they break again.
If you have an 18 spline unit we can modify the case and gears to accept the 25 spline version. Same with the t-case coupler.
WARNING: If you stripped the splines and tried to drive the car your VCU (viscous coupling unit for the center diff) may be damaged. When the shaft breaks, or the splines strip, the car will feel like it has a slipping clutch. This is due to the fact that all of the power is now going through the VCU which is working hard to try to put the power to the front wheels as no more power is reaching the rears. If this happens and you don’t immediately stop, the VCU will be toast and they are near impossible to find. We try to keep some in stock for our customer trans rebuilds, but avoiding the problem is really the best way to go. Back when you used to be able to find them new they used to retail for $1600, so even today used VCUs go at a premium price.
Here is a picture of a shaft with worn splines on the left and good splines on the right:
Burned up VCU: