« Reply #34 on: October 01, 2014, 06:26:39 AM »
The front driveshaft has to be lengthened (or "shimmed" to keep it from compacting and sliding out) with either NP242/231 correct?
Would the rear driveshaft (has a slip joint) be able to be used in place of the front driveshaft on the Eagle? If memory serves me right, when I compared the driveshafts I have sitting at home it came out a few inches longer and the ujoints looked the same.
The rear driveshaft is considerably longer and a much thicker diameter.
The front driveshaft does not have to worry about compacting and sliding out. That is only for the rear driveshaft because two slip joints add up and slide out the back of the transfer case. In the front you have a yoke on either side, not a slip joint.
If you just swapped the stock NP129 for a NP242 you would use the Eagle front yoke and not need any other changes up front. In the rear you would need a 3" spacer. Since you are doing an AW4 swap at the same time the transmission will be 3" longer. Hopefully that eliminates the need for a spacer in the back. I'll be able to tell you for sure in about a week since this is how I'm currently doing my AW4 install. In the front you have an inch or two of adjustment in the slip yoke but it is probably not enough to make up for the longer transmission. I plan on using an XJ front yoke which is an additional inch or two longer than the Eagle one. The added length of those two together should make the front driveshaft work as is. The XJ front yoke has different Ubolts that may provide complication. I think they are meant to go through unthreaded holes and have nuts instead of bolts that thread in.
Logged
Currently Inspected and Insured as of Jan 2013:
-1985 Eagle Station Wagon 258 T5 Stickshift
-1980 Eagle Station Wagon 258 Auto Fuel-injected with GM TBI
Minor Repairs Underway:
-1982 Eagle SX4 258 T5
-1981 Kammback 2.5L Iron Duke T5
Restoration Efforts Near Completion:
-1982 SX4- 401 NV3550
-1983 SX4- 4.5 MPI NSG370 (6 Speed)
Restoration Efforts Underway:
-1985 SW- 4.0 MPI AX15
-1982 SX4- 4.0 AW4
-1981 SX4- SD33T NV4500 (Turbodiesel 5 speed)
Future Rescue Efforts- '85 Maroon SW, '87 Limited SW, '84 Limited SW, '87 4 door Sedan, '81 2 door Sedan, '88 White SW, '77 4 door Hornet, '74 2 door Hornet, '79 Spirit AMX, '81 Kammback.
RIP- Red '81 SX4, '84 4dr Sedan, '84 SW, '81 SW, '80 Spirit, '83 SW, '83 4dr Sedan