154 9811 Boneyard Tranny Swaps - old And New Shaft - Photo 29822408

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Out with the old, in with the new. The new shaft will accept all of the gears and assemblies from the old shaft. It is shorter and contains a spline size that mates directly to the Dana 300 transfer case. Be sure to check for proper endplay and clearances required for proper oiling.

154 9811 01 o+154 9811 boneyard tranny swaps+working on the tranny

The Advance Adapter kit works with both the two- and four-wheel-drive gearboxes, and includes a new mainshaft, adapter housing, gaskets, seals, and instructions.

Remove the top cover and integral shifter and linkage. This 4WD version was purchased without the tailshaft assembly. The tailshaft was not required, saving us $50 on the initial purchase price.

nap-ring pliers are a must to remove the snap rings that retain the rear bearing assembly. Be sure to check the assembly for wear, and replace as necessary. This one was within acceptable limits, but was replaced as a preventative measure.

Remove the rear bearing and spacer as part of the process to remove the entire mainshaft assembly.

The next step is to remove the front bearing retainer. Again, inspect the bearing and retainer for excessive wear. Plan to replace the seal inside the retainer.

Carefully remove the input shaft. Use caution to avoid any of the residing needle bearings or other parts of the assembly from falling into the case.

The mainshaft can now be removed as a complete unit and can be disassembled in an orderly fashion-this will be of great assistance when installing the new mainshaft assembly.

Gear and synchronizer assemblies don't need to be completely disassembled unless further R&R is required. Simply remove them from the original mainshaft and prepare them to be placed on the new shaft.

This is First and Reverse gear. Be sure to note the placement of the two small flat springs located inside the gear.

Proper placement of the flat springs will become one of the most important parts of the re-assembly process.

Removal of this two-piece snap ring will allow for the final disassembly step.

Out with the old, in with the new. The new shaft will accept all of the gears and assemblies from the old shaft. It is shorter and contains a spline size that mates directly to the Dana 300 transfer case. Be sure to check for proper endplay and clearances required for proper oiling.

Re-assembly is relatively simple. Replace the gears, synchros, and snap rings in the respective positions they occupied on the original shaft. As mentioned earlier, strategic placement and a few notes during disassembly greatly aid re-assembly.

The new shaft and all related parts were assembled in less than 10 minutes and ready to be placed back in the case.

Carefully insert the new mainshaft assembly. Be sure to have all the needle bearings in the input gear in place. A small amount of grease will hold them. The front-bearing retainer and rear bearing can then be installed.

Proper assembly will allow for the snap ring to be positioned.

Use the provided gaskets and hardware to install the adapter housing. The housing is machined to work on both the two- and four-wheel-drive tailshaft patterns. It is also machined and threaded to provide a mounting surface for a tranny mount.

Due to the larger dimensions of the NP435, the transfer case shifter mount and linkage is a close, comfortable fit. Notice the fill and drain plugs and the production tag on the NP435

The tag will be important if and when replacement parts are required. Check possible donor gearboxes to be sure the tag is present. It could save a lot of time and work later.