Project LBMC
Ultimate Transmission Build
Published in the September 2013 Issue
September 2013
Transfer Case Inspection
The input shaft on the transfer case has to be replaced with a 29-spline shaft. The stock shaft is a 23-spline for the automatic transmission truck and a 29-spline for the manual transmission truck. Some transmission shops simply take the 23-spline input shaft out of the transfer case and machine a slot across it to accept their “plug welded” transmission tail shaft.
This is a cheap way to try and make the tail shaft of the transmission stronger, but ultimately it is nowhere as strong as the proprietary billet 29-spline shaft that Ultimate Transmission uses. When we disassembled the transfer case we found that one of the thrust bushings on the shift fork was not installed properly and needed to be replaced.
Once the transfer case is disassembled, it’s off to the parts washer. After a good cleaning, the transfer case parts get inspected then prepped for reassembly. All new bearings and seals are used along with the 29-spline input shaft for the manual transmission trucks.
The components of the transfer case are carefully put together and checked for proper thrust clearances.
All of the stripped/broken bolts were taken care of and the cooler line and flex plate were replaced to assure a trouble-free transmission.
Once everything was repaired or replaced, the transmission was ready to install.
After all the bolts, cooler lines, wiring, covers, and shift cables are installed, the transfer case is lifted into place and bolted onto the transmission.
Drive lines, cross members, skid plate, and wiring is installed on the transfer case; then fluid is added.