Changing the engine in a Jeep

jeep
diesel
engines

#1

I have 2007 Jeep Wrangler X, 6-cyl engine, 6 speed man-trans. I want to exchange my current gasoline engine for a diesel engine. Is this even possible? Would there be any subsidiary work, such as, changing drive-line components, or transmission adjustments that would be required?


#2

Since your transmission will not bolt up to any diesel suitable for your Jeep, you will need to replace that too…Oh, wait, If you live in an emissions test area, engine swaps are out of the question.


#3

This would be a major custom modification. It is possible but you’ll need lots of money and a well equipped garage. Some special skills with welding to change the frame mounts for the motor and transmission and chopping the drive shaft(s) maybe required.

This is not a casual motor swap. The gear ratios of the transmission and differentials are suited to a gas motor and will not optimize the performance characteristics of a diesel.


#4

Interestingly enough, the Wrangler sold overseas can be had with a 2.8L 4 cylinder turbo diesel that makes 174 HP and 302 lb-ft of torque. Fuel mileage isn’t as good as you would think though. It only gets about 2-3 MPG better than the 3.8L gas V6.

While possible, the swap is not a sensible one, the six speed manual should bolt up (the Euro-spec Jeep has the same transmission for the gas and diesel engines), you may need an adapter though. You will also want to change out the front and rear diff gears for something taller to take advantage of the diesel’s low end grunt and lower operating speed. Figure about $1500 or so for that. A quick check of Ebay UK tells us that the going rate for a used Jeep 2.8L Diesel engine is about $2500 USD. You may or may not be able to use the accessories off your gas engine so keep that in mind as well. There will be some custom fabricating involved, new motor mounts and such. So figure in another grand or so for that, maybe more. You also may need to have your driveshafts lengthen or shortened, depending on how everything fits together. So right now you at around $5000 USD best case scenario. Major swaps like this one have a habit of not going according to plan, so realistically you’re looking at spending closer to $7-8k USD, possibly more.

In exchange for the estimated $7k-$8k, you will be getting more torque, less horsepower, and about 2 or 3 more MPG. Your warranty will be void obviously, and your Jeep will no longer be street legal in many parts of the country.

Your call


#5

Actually, his Jeep won’t be street legal anywhere in the US since it will no longer have its original emissions equipment, it’s just a matter of whether he lives in a state that checks.


#6

Wow! I want to thanks everybody for the input. After hearing all that, especially with the limited gas mileage increase, which was, I suppose the theoretical upshot here anyway, I don’t think I’ll be looking to try an engine swap on this particular vehicle anytime soon. I live in NY, our DMV is the dickens about emissions testing, and all the transmission mod doesn’t really seem like anything I’d want to do to a mint condition, warranteed vehicle.
Thanks again all.


#7

Visit jeepforum.com.