Diesel conversion

[REDLEG]

Just got my first Jeep, a 93 with a bad engine and a good body (paid $1500.00). I am going to do a frame up restore,using a cummins 4bt3.9L diesel and a 700R auto transmission. (Jeff Daniels Jeep is doing this part). Has anyone in this forum done this conversion, or knows of someone who has? Thank you for any feed back.

 

[BaconYJ]

I have been interested in this kind of conversion for awhile now. Couple sites i have found which should help you greatly.

Cummins 4BT & Diesel Conversions Forums - Powered by vBulletin

Garrett's "Marshtackie" - My Jeep Club

1993 Jeep Wrangler YJ Cummins Diesel Engine Swap - Diesel Power Magazine

3.9L cummins in Jeep Wrangler?????? - Diesel Power Forums at Diesel Power Magazine

Keep us informed on what and how you do this converion please. And MOST importantly post PICTURES!!! (pop-up ones that move are even better)

Bacon

 

[Bounty__Hunter]

WELCOME TO JEEP2DIESEL.ORG

 

[Ggg]

I did.
Started with a 98 TJ bad engine. Started out using the TH475 that came with the engine but changed my mind and used the AX-15/231. I replaced the axles with a Sterling 10.25 and a high pinion D60, detroit lockers in both. I am running 38" tires.

 

[BaconYJ]

What is the gearing you are running in your Jeep with the 3.9bt? I am looking to try and hit 65-70mph highway to get to and from the trails max.

Bacon

 

[Ggg]

I am running 5.38 gears, I am not worried about highway speed. There aren't any trails close by so it will get towed to and from.

 

[Levinoss]

Is it really worth going diesel? With Diesel so expensive now?

 

[Wrangl3r93]

The jump in gas mileage is amazing. A friend of mine has the 4bt with a larger hy35 turbo. He claims to get 35 mpg cruising at 65 and 30mpg cruising at 70. He's also not worried about his gearing with over 600ft/lbs of torque. I've raced him with the 4.0 and he left me in a cloud of black smoke

P.S.- It took him a while to find axles strong enough to hold up. He was snapping them like toothpicks

 

[BaconYJ]

I could believe he was snapping axles. I should be ok there... Ford 79 D60 with 35spline inners and outers and a 14bolt. Both Detroit locked with 5.13s. Would be using a SM465 transmission when I eventually (2years or so) get around to doing this swap.

Bacon

 

[Ggg]

Is it really worth going diesel? With Diesel so expensive now?

The reason I did mine is I am a heavy diesel mechanic, so diesels are sort of second nature to me. The only gas engines I own are my chain saws. I agree looking at the engine swap from purely a MPG/ fuel cost savings point is debatable at best. I know quite a few who have swapped this same engine into a wide variety of vehicles and MPG will vary greatly for a given type of vehicle. There are other engines that would yield much better economy but would not be the best for my application (low rpm torque).