CJ5 with a TH400 trans.

[Dons78CJ5]

I just got a CJ 5 project Jeep the other day and one of the bigger problems is someone along the way has converted the CJ from manual to auto transmission. After doing a little research I found that the TH400 is not what you want due to length. The drive shaft angle is extreme and probably cause problems. I just got that engine running but have not checked out the rest of the drivetrain.
My question is should I save time and try to fine a TH350, or even go back to manual. I'm old school and a manual trans is not a problem.

 

[Tinman22]

Th 400 isnt really a problem if its done properly. What exactly is your driveline? 304, is it an amc 400 or a gm variant with an adapter ring? If amc is it clocked or not? What t-case do you have? Is it a quadratrac case or a dana300 or something else? And what rear axle?

Currently swapping out the black jeep driveline. 350/465/300 for 325/400/300 using the same driveshafts.

Th400 to th350 is only 2.62” difference

 

[Dons78CJ5]

The Jeep is new to me. What I'm sure of is the engine is a 304. The Transmission is a BOP TH400.
There is a adapter between the two, but it looks like it came that way.
Transfer case is straight through to the rear drive so I think it's a Dana 20?? I'll do some more checking when I get back to the house. I'm work right now. The guy I got the Jeep from was not much help on the history of the Jeep. There is a clutch peddle zip ties under the dash. It has a Hurst ratchet shifter mounted on the trans tunnel and the steering column does not have a indicater like a factory auto trans Jeep would of had.
Thanks

 

[Tinman22]

I think Bop th400’s came in some fsj’s with adapters for amc engines but thought they were all quadratrac. But hey anything can happen in30 someodd years. Can you get some pics?

 

[Dons78CJ5]

I think Bop th400’s came in some fsj’s with adapters for amc engines but thought they were all quadratrac. But hey anything can happen in30 someodd years. Can you get some pics?

Just got to the house. Does the site host pictures are due I upload them to a third party?


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[Dons78CJ5]

 

[Dons78CJ5]

Posting pictures is no fun. Lol
If you go to my gallery you can see what I've uploaded so far.
Thanks again.

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[jp360cj]

I just got a CJ 5 project Jeep the other day and one of the bigger problems is someone along the way has converted the CJ from manual to auto transmission. After doing a little research I found that the TH400 is not what you want due to length. The drive shaft angle is extreme and probably cause problems. I just got that engine running but have not checked out the rest of the drivetrain.
My question is should I save time and try to fine a TH350, or even go back to manual. I'm old school and a manual trans is not a problem.

What kind of issues are you having? If it's driveline vibrations, then it probably is the driveshaft. Can you get some pics of the driveshaft? If you have any lift, you'll almost certainly need a double cardan (cv) rear shaft IF you can get the angle low enough for it to work. Tom Woods has some good info in the tech section of his site (Tom Wood's Custom Drive Shafts - Tom Woods Custom Drive Shafts Custom Driveshafts Specialist)

Also, how much lift do you have?

Th 400 isnt really a problem if its done properly. What exactly is your driveline? 304, is it an amc 400 or a gm variant with an adapter ring? If amc is it clocked or not? What t-case do you have? Is it a quadratrac case or a dana300 or something else? And what rear axle?

Currently swapping out the black jeep driveline. 350/465/300 for 325/400/300 using the same driveshafts.

Th400 to th350 is only 2.62” difference

Are the 465/adapter and 400/adapter the same length or are other changes neccesary to keep the same shafts? also, whats your wheelbase? The OP has a 83" wheelbase CJ5.

I think Bop th400’s came in some fsj’s with adapters for amc engines but thought they were all quadratrac. But hey anything can happen in30 someodd years. Can you get some pics?

I think all of the FSJs with TH400s were quadratrac.

72-73 Commandos had TH400s and D20s but idk if they were a bop or amc case. The older Commandos were available with a Buick V6, bop TH400 and D18. A Dana 20 is a direct swap for a D18.

 

[Dons78CJ5]

I have uploaded a few pictures in my gallery.
I have not figured out how to post pictures here yet.
I have not driven the CJ yet and it may drive fine. My concern was when I got the CJ home and was crawling around under it to fix a fuel line issue I noticed that the factory BOP adaptor plus the TH 700 plus transfer case mad e for a real short driveshaft. I'd say less than a foot long and very steep Angeles on both ends.
I did get one picture of the drive shaft uploaded.
Right now I'm working on getting the engine to run smoothly. Some one stuck a high lift cam and 4 barrel and aluminium intake. They removed the vaccum advance at so point so I need to replace that also. I hope to get the motor reliable this week and then address the drive line issues.
Again thanks to all who responded.
I may pull the whole drivetrain out and slide a manual setup in it.

 

[007]

It would seem that you’re driveline was shortened by way of not using a Quadratrac.

I too would have shaft balanced.


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[Dons78CJ5]

It would seem that you’re driveline was shortened by way of not using a Quadratrac.

I too would have shaft balanced.


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I'm not sure where the 304/th400/transfer case originally came from.
I need a vin number decoder to check and see what it was when it left the factory. Not that it really matters, I will either fine a way to make it work or find something that will work.
It was a project Jeep and has had a bunch work done on it.



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[jp360cj]

It would seem that you’re driveline was shortened by way of not using a Quadratrac.

I too would have shaft balanced.


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If anything, I would expect the Dana 20 to be shorter than the q-trac. Although a q trac would offer a little less driveshaft angle with the dropped rear output.

His driveshaft was shortened because a TH400 was stuffed into a CJ5

 

[007]

If anything, I would expect the Dana 20 to be shorter than the q-trac. Although a q trac would offer a little less driveshaft angle with the dropped rear output.



His driveshaft was shortened because a TH400 was stuffed into a CJ5

That’s my point... the shortening necessary to make a 400 work in a 5 was partially accomplished by not using a QT.

Either way what he has should be able to work.


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[Dons78CJ5]

 

[Dons78CJ5]

This is not the best picture but it should give you an idea of the angles.

 

[jp360cj]

That’s my point... the shortening necessary to make a 400 work in a 5 was partially accomplished by not using a QT.

Either way what he has should be able to work.


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Oops, I misunderstood. I thought you meant the driveshaft was shortened by using the Dana 20 instead of a Qtrac.

 

[mtnwhlr]

Unless you are in love with the auto trans I would ditch it and find a T-176. My CJ5 came stock with a T-176 and Dana 300.

 

[Dons78CJ5]

Unless you are in love with the auto trans I would ditch it and find a T-176. My CJ5 came stock with a T-176 and Dana 300.

Just looked up the T-176/Dana300 specs. Much better set up I think. I'll start looking around for a donor.

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[Peanut Butter]

You may want to read this if you already haven't.Jeep TH400 Technical Information - Jeep-CJ Forums and this,Is your CJ Original? Maybe Not! "Heavy with Pictures" - Jeep-CJ Forums