a cummins going into a TJ

[drivers]

So i have my stock 97 TJ, with the 4banger in it, one of my industrial mechanic instructors suggested i put a in-line 6 cummin in it. he put one into a suberbon and told me it would be awsome in my jeep, with that much weight and extra power i am assuming i would have to beef up the susspention, axils, transmission, trans case
Have any of you ever attemted this or know of any major issues that i should be conserned about before i dive in?

 

[gearheadmb]

I don't think a 6 cyl cummins is a good idea at all. Its a great engine but yes, way too heavy and way too much power for the drivetrain. A 4 cyl cummins would be alot better, but still would probably be too much power for the stock drivetrain,and you would really have to know what you were doing to make it all work together. Its one of those things that if you have to ask you probably shouldn't do it.

 

[drivers]

i love the idea of doing this and i relize it would be a huge deal to do
and i relize i would have to do alot of work to make it right but i am able to park my jeep for long periods of time because it isnt my every day driver
but where would i start looging for a 4 cyl cummins?? all the ones i have found have been 6.

 

[xjmarc]

Bread trucks and such run the Cummins 4bt. A 6bt would weigh a ton and would be too long to fit without remoteing the radiator and cutting the fire wall. I have one in my tow rig and they are huge.

 

[myjeepdestroys]

Love the idea even though you wouldn't use anything stock. Get some d60s and have fun. If you got the money then run diesel

 

[Ggg]

I have a 4bt in my TJ. The 4bt is plenty of engine, capable of more than 600 h/p. The 6bt will fit without any firewall or radiator position mods but it is very heavy, and a tight fit. The 4bt weighs about #800, and the 6bt #1100 depending on what engine options. I used 1 ton axles, AX15/231sye, and 37" to 41" tires. The 4bt swap is not cheap, but a very impressive engine on and off road.

 

[jfrabat]

I run a Toyota oil burner (Fortuner; model not sold in the US) and let me tell you, a 4 cylinder diesel is more than enough power. And yes, even with the 4 cyl diesel, you will need a stronger transmission than the AX-5 and probably need to get rid of the D35 as well. The TC you can keep, and I think the D30 should hold up fine.

 

[Ggg]

What is your intended use and tire size after completing the engine swap?

 

[jps4jeep]

it's been done, it's a very tight fit, will require firewall cutting and a body lift as well as some pretty beefy suspension and axles. I concure, 4bt would be a better choice.

 

[drivers]

the intended use for the jeep after is to be a weekend warrior nothing extream but have some fun with my son in the truck i have done a bunch or reaserch since my first post and found a few people that have done the swap, i have also found a 3.9 my buddy has a chip delivery truck that got totaled and i have pulled the motor and started the rebuild on it, i am going to use the rear and front end off a ram 1500 truck so i can use my rims and tires i had off my 91 f-150, i have not found a transmission yet because i dont like the GM 3 speed auto that was in the chip truck, so far i havent spent much money just my time my buddy gave me the motor and the front and rear end i can get from my uncle
ill keep you all posted on progress

 

[drivers]

oh the rims and tires i plan on using are 15x10.5 rims with 33x12.50 tires i may have to go bigger with tires just to keep the rpm down on highway but i want to keep it as small and cheep as possible

 

[Ggg]

Be sure the rim bolt pattern is the same. Most dodge 1/2 ton bp are not the same as Ford 1/2 ton bp. There are a few exceptions though, I have a set of Dodge Ramcharger rims on my Cj2a which has the same 5 on 5.5"bp.

 

[drivers]

thats what the bolt pattren is is 5 on 5.5" the only thing that may be a issue is the off set of the rims

 

[zatog]

So how did the conversion turn out i'm just wondering because i was thinking about doing the same conversion.

 

[Ggg]

Here is a link to a good site with lots of diesel swap info.
Cummins 4BT & Diesel Conversions Forums