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Discussion Starter #1
Hi, I am in the U.K. and have had a jeep (1999) for some years, an old friend told me that after WWII it was common to convert engines from petrol to diesel getting greater MPG and Horses he mentioned two engines a detroit v8/v6 diesel (2 stroke), or 3 cyclinder straight. Does anyone know if this can be done, without changing the transmission and clutch?

Petrol here is now £1.15 per litre (about $2.00 I think)

Detroit Section Caretaker
3,761 Posts

If you're considering swapping the old engine in your jeep for a Detroit Diesel, then start out with a tape measure. Even the "smallest" (53 series )Detroit V8 and V6 engines are really big in comparison to a jeep.

A more realistic engine, but perhaps still on the heavy side would be a 3-53, which is three cylinders.
An easier swap may be a 2-53, two cylinders, but may not have enough HP to be a worthwhile swap.

You may be able to use the original transmission with a custom made adapter, and the clutch if you re-drilled the flywheel to suit, also make a pilot bushing, this is probably the difficult way to go about it.
May be simpler and better off to use a readily available and simply bolt on transmission and clutch. What to use all depends on what you have, what you can get, and what you want to do with the vehicle.


1,384 Posts
I originally wanted to put a 4 cylinder diesel in a jeep when I first joined here. After hearing some people here, they would say its foolish to put a big engine in a jeep.

I bought a 53 series engine manual and learned about there dimensions. The 3-53T Silver is the biggest engine you are going to get in there.
But its going to take a lot of modifications.
The Dana 30's on the front are going to pose a problem with the oilpan.
Some have mentioned that it is possible to reverse the oil pan on some Detroit inline models to allow for differential clearance.
But please note, the 3-53NA alone is taller than the engine compartment by about 8 inches.
The only way to get it to fit and maintain 4WD is to put a liftkit, or mount the engine behind the front diff.
A better option may to go to 2WD for a better fit, while maintaining "stock" look

I am still pursuing the idea, but I have yet to own one of these Detroit monsters.

It has been done. There is a guy named Ronnie in Oklahoma who put a 3-53NA gamma goat engine in his 74' CJ

One other thing to check is whether the Dana 35 rear's can take the torque of the Diesel. I do not know whether its strong enough.
You are not going to be able to use the stock automatic transmission, if you have one. The only Automatic I know of which can be used with a Detroit is the Allison 4L80 series

I may not be getting everything right, I am 19 and learning as well


751 Posts
that cj with the 353 is nuts.

i would love to be in the room when you try to stuff a 8v into a tj. the term 5lbs into a 3lbs bag comes to mind.

57 Posts
2 stroke detroit in a cj

I got a gas engine too hot in my 48 cj2a when it slipped a water pump belt while driving through the ranch about 1 year ago. Had coolant in the oil and before you know it I had the perfect excuse to swap in a diesel.

I ultimately decided, after wearing out a tape measure, to go with a 2-53. I found one that was seized and put in new bearings, pistons, and liners, and rebuilt the blower. The short version of the story is:

I changed transmissions, rebuilt a big shaft SM420
retained the oem transfer case but rebuilt it
retained the oem axles
used the gama goat bell housing on a #3 flywheel housing
modified the input shaft on a big shaft SM420 to fit the flywheel
purchased an adapter to bush the 4 speed SM420 to the oem dana 18 from novaks (high dollar, but well made).
everything but novaks adapter was $100 here, $100 there. Not too bad.

I would project that I am past the halfway point in this project. Pay heed to Grigg's advice that you should not be in a hurry on something like this. But it will be completely worthwhile if you don't watch the clock.

I am muddling through brake and clutch linkage issues and driveshaft lengths right now, but the drivetrain is in position and I am satisfied that it is adequately mounted.

Steering and exhaust have yet to be completed, but I'll work that out when the time comes.

If you are a good body man, or know one, you might go with the 3-53. The 2-53 hp designation matched the gas engine I was replacing, and I am guessing that a xx hp detroit would outdo an xx hp anything else, since they are bent towards industrial applications and not just peak hp. Don't forget that overdrives are made for many of the jeep tcases, and a later jeep might have a number of different axle gear ratios to choose from.

Good luck with your project, and I am less than a year away from saying, 'It can be done!'.

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