Tweet
I have a 74 J20 with a factory 401/T18 4 speed. The Dana 20 transfer case needs to be rebuilt. I also have a 1980 J10 parts truck, it is a 6cyc with a 4 speed transmission and a NP transfer case. Question is can I swap out the transmission and transfer case into the 74? Is the 1980 set up any better that the 1974? Thoughts?
-
74-J20 401/4-speed
79-Waggy 360/auto
86-Gwaggy 360/auto
14 JKU -
D20 is passenger drop front axle/transfer case.
80-up NP is driver drop front axle/transfer case.
More involved than just a simple swap...
Also 6cyl t18 will have short input shaft vs v8 having long input shaft and uses a spacer.Tony
88 GW, 67 J3000, 07 Magnum SRT8 -
I guess the best question is "why"...? What is to be gained with the 80 model trans and tcase?
J20
BP Drivetrain...........
Driveshafts for all Jeeps, Constant velocity rebuilds, Replacement, Repair
775-537-7918
https://www.facebook.com/BPShafts/
Putting this back up. "Someone is gonna have to crawl under the rig"Comment
-
Here's the rebuild parts...Or you could just get another tcase and put it in.
J20 BP Drivetrain...........
Driveshafts for all Jeeps, Constant velocity rebuilds, Replacement, Repair
775-537-7918
https://www.facebook.com/BPShafts/
Putting this back up. "Someone is gonna have to crawl under the rig"Comment
-
The V8 transmission is longer than the 6-cylinder transmission. Look under the Jeep and you'll see the long adapter on the T-18 that fits a V8 truck. No adapter on the 6 4-speed. An '80 4-speed is a T-176, completely different from the T-18. The T-18 is much, much stronger than the T-176, which is hardly up to V8 power in a J20. The T-176 is close ratio, like a passenger car transmission. No granny gear. The 80-up tans/TC drops on the opposite side, and won't work with the '74 front axle. You'd have to swap axles and then you'd made a J20 into a J10. Lots of reasons to discard this idea out of hand.
The Dana 20 is a good transfer case, replacement units are widely available and they are easy to rebuild. A '74 J20 with a V8 and T-18 is a great combo which you should keep and be proud of.
Also the only year the 401/T-18 combo was available. Great stuff.Last edited by tgreese; 09-02-2020, 05:15 PM.Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination ATs, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
ECO Green: '15 FCA Jeep Cherokee KL TrailhawkComment
-
I mean...you have a Dana 20, which is a cast iron gear drive transfer case. Strong, simple, hard to kill, does it's job and doesn't complain.
Why you'd want to replace it with some aluminum chain driven thing is beyond me. I've had the chains stretch with age and start whipping around in the case causing vibration at highway speeds.'72 Jeep Wagoneer Custom, 360 V8
I love how arguements end as soon as Ristow comments. Ristow is right...again.Comment
-
you'll spend more money trying to put the newer weak setup in your truck,over rebuilding the dana 20.Originally posted by Hankrod
Originally posted by Fasts79Chief
Originally posted by Fasts79Chief
It's like you're unraveling a big cable-knit sweater that someone keeps knitting...and knitting...and knitting...and knitting...Comment
Comment