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73JeepGuru
08-19-2016, 08:00 AM
I'm looking at buying a nice 74 j10 with a 360 and th400 with the quadra trac t case. I am wanting to swap the tranny and t case out and put a t18 in with a Dana 20 t case. What fabrication or other parts swapping would this entail? Rear axle, driveshafts? Any info would be greatly appreciated, lots of detail is great too, thanks!

tufcj
08-19-2016, 10:51 AM
You'll need a 360 specific flywheel. AMC V-8 engines are externally balanced, so flywheels are specific to displacement. You'll need the bellhousing from a Jeep truck or Wagoneer that has about a 6" spacer on the back. You'll need the pedal set (it should swap into the bracket under the dash) along with all the associated linkage and brackets. Clutch and pressure plate. The T-18/model 20 is considerably shorter than the 400/q-track so driveshafts are different. The q-track rear is offset, you could run it although the centered rear would be better for u-joint life. You'll want to add hubs to the front axle. You'll need to cut out the floorboard and install a cover plate with the correct boots for the 4-speed and t-case. The best bet would be to find the T-18/model 20 J truck or wagoneer and get all the parts from a single donor. Jeep CJ parts are different.

The best solution might be a part-time kit for the q-track - if they're still available. It also provides a slight overdrive.

Bob
tufcj

73JeepGuru
08-20-2016, 11:00 AM
I appreciate all the advice and info! I actually just came across a 71 j4000 with a 360 and a 4 speed

tufcj
08-21-2016, 07:20 AM
The 71 flywheel won't fit the 74 engine. AMC made a change to the rear of the crankshaft in 72 to make the Mopar Torqueflite torque converter fit. In the trucks that used the TH400 there is a thin spacer pressed into the back of the crank for the GM converter. You will have to remove that before pressing in the pilot bushing. You could just swap the entire engine/trans/t-case and be done.

Bob
tufcj

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