Cummins swap discussion

[john adams]

If you're thinking of swapping a Cummins from a 3/4 or 1 to Ram into a JL, you should reconsider. Just getting the engine to fit will require major surgery. It's a long engine that won't fit without a lot of cutting and welding. Dealing with the cooling stack on top of that is also a big challenge. There's no way you're going to have enough air flow to cool it without a significant redesign of the grill.

But if you really want to make it fit, it can be done with enough money.


A smaller diesel like the Cummins R2.8 is a lot easier to fit and has lower demands for cooling. Getting it to mate with the transmission and getting the computers to play nice with each other may be a significant challenge. Going with a different transmission and transfer case may be easier in the long run.

As has been mentioned, most of these swaps aren't exactly within emissions laws so depending on your location, they may not let you register the swapped vehicle.

Engine swaps can be a lot of fun. I've done a couple. Just be prepared to spend way more than you thought you would.

Considering? Not so much. I am looking down the road. It's been mentioned a couple times, once recently, and I thought it sounded like an outrageous project, but I wondered if anyone had actually done it or it was just a pretty crazy option. Sounds like the latter.

Thanks a lot Jeep for making a 3 year run on my truck.

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[mwilk012]

Considering? Not so much. I am looking down the road. It's been mentioned a couple times, once recently, and I thought it sounded like an outrageous project, but I wondered if anyone had actually done it or it was just a pretty crazy option. Sounds like the latter.

Thanks a lot Jeep for making a 3 year run on my truck.

You’re better off planning on an EGR / DPF delete than any sort of engine swap. The engine will last a very long time if taken care of.

 

[grimmjeeper]

Considering? Not so much. I am looking down the road. It's been mentioned a couple times, once recently, and I thought it sounded like an outrageous project, but I wondered if anyone had actually done it or it was just a pretty crazy option. Sounds like the latter.

Thanks a lot Jeep for making a 3 year run on my truck.

Yeah, my plan is to maintain my Jeep as best as I can going forward. The engine should last for a while assuming I'm not in the small group with early failures. Given this engine was also in the Ram, it should be supported for a while. If it dies completely, I'll decide between a replacement, a rebuild, or letting someone else enjoy it while I get something else.

With all of the modern computers in vehicles these days, a swap to a different engine is more work than I want to deal with. So no swap for my JL. If I'm going to swap another vehicle, I'm going to stick with a carburetor era one. Way easier.

 

[BDinTX]

I was casually looking into this myself. The only Cummins swap JT I could find was a JT body put on a Ram truck frame and drive train. Everything else I found were older jeeps that didn’t have to deal with emissions requirements.

Physically the Cummins 2.8 seems like it would fit and they sell it as a crate motor but stock, their power output isn’t that great. Their 5.0 v8 that went into the Nissan Titan might also fit but you’re just trading one short run problematic engine for another.

As mentioned, with any swap the programming and emissions would be really hard to pull off so you’d likely end up with an off-road only vehicle that has basic gauges, analogue controls, and is nowhere near the same vehicle it is today.

Unfortunately, it seemed like it would be easier to pull off a hemi swap. My pockets aren’t deep enough to do any of it so I’ll just run the wheels off of it as is.

Hopefully there are replacement motors when the time comes.

 

[21JLURDG]

It seems like others have had the same worries I have about possible future catastrophic engine failure. The larger diesels (5.9-6.7) are just impractical to make them fit. The smaller diesels (VW 1.4 to Toyota 4.5) make less power than our stock 3.0, so even with a workable swap it would feel wrong.
If my engine dies with plenty of life left on the rest of the vehicle, then I think two possibilities are:
1. Get another new or rebuilt ecoD 3.0
2. Explore the possibility of swapping to another JL gas engine, such as the new Hurricane 3.0 I6. Emissions laws would be a problem.

 

[ALeeL]

Cummins still makes a turn key 2.8L. It is way down on power compared to the Ecodiesel, but that is due to the emissions tuning since it goes through a more stringent engine dyno certification and not a chassis dyno certification like complete vehicles do.

https://www.cummins.com/engines/repower

If I were to ever swap anything into my JL, I would put a BMW M57 3.0L inline-6 turbo diesel engine. Those things are bullet proof even at high horsepower and already mate up to the ZF 8-speed transmission. I have seen them at over 500 rwhp with stock internals.

Unkillable Diesels: BMW’s M57 I-6 | DrivingLine

 

[mwilk012]

I was casually looking into this myself. The only Cummins swap JT I could find was a JT body put on a Ram truck frame and drive train. Everything else I found were older jeeps that didn’t have to deal with emissions requirements.

Physically the Cummins 2.8 seems like it would fit and they sell it as a crate motor but stock, their power output isn’t that great. Their 5.0 v8 that went into the Nissan Titan might also fit but you’re just trading one short run problematic engine for another.

As mentioned, with any swap the programming and emissions would be really hard to pull off so you’d likely end up with an off-road only vehicle that has basic gauges, analogue controls, and is nowhere near the same vehicle it is today.

Unfortunately, it seemed like it would be easier to pull off a hemi swap. My pockets aren’t deep enough to do any of it so I’ll just run the wheels off of it as is.

Hopefully there are replacement motors when the time comes.

The easiest performance swap will always be for the 6.4. The parts are all available from the factory and the fitment is exact. The 6.2 is not so bad either, it can be done within reason. LS swaps are not worth it at all, the Hemi is so much better it isn’t worth it. LS engines aren’t cheap like they used to be.

 

[Pape]

I've seen a few people here suggest that when their Ecodiesel engine dies (or before), they might swap out for a Cummins. A few questions from someone who never swapped a diesel engine:

1) How possible is this? I mean, is this a realistic option to keep the vehicle going? OR is this going to create more problems since the Wrangler isn't built for that engine?
2) Someone suggested a total parts and labor cost of $15,000. Does that sound realistic?
3) Would that significantly prolong the life of the vehicle? I know the engine would be good after that, but would it be putting a 13 year old's heart in a meth addicts's body? Meaning, would this effort be worth it while the rest of the Jeep falls apart?

I like my 2023 and I'm already at 50K no-issues miles...but Jeep has a dubious reputation.

Everything is possible to certain degree, I would say look for a kit you will have a higher chance of acceptable result. Worse case the JL become a project Jeep.

 

[grimmjeeper]

The easiest performance swap will always be for the 6.4. The parts are all available from the factory and the fitment is exact. The 6.2 is not so bad either, it can be done within reason. LS swaps are not worth it at all, the Hemi is so much better it isn’t worth it. LS engines aren’t cheap like they used to be.

 

[mwilk012]

Without a doubt. Comparing like to like, of course. 5.3 to 5.7, 6.2 to 6.4, the Hemi drives so much better, and I don’t even own one. I have a Chevy.

 

[Gregj]

If I were to ever swap anything into my JL, I would put a BMW M57 3.0L inline-6 turbo diesel engine. Those things are bullet proof even at high horsepower and already mate up to the ZF 8-speed transmission. I have seen them at over 500 rwhp with stock internals.

Unkillable Diesels: BMW’s M57 I-6 | DrivingLine

Those things do have the potential for big power but that article glosses over the fact they tend to spin the number one main bearing. My brother has three of them and two have spun the main bearings.
Gregj

 

[Tread4Lo]

I know everyone loves to talk motor swaps. Maybe it's all fun and like a pipe dream. I see this motor as take care of what you have because it's always going to be a helluva a lot cheaper.

If we are scared about longevity, you need to just delete the emissions and call it a day. Then you get into the "who is going to buy it, it won't be the dealership". Wouldn't you run into the same issue with a motor swap too? No dealership in their right mind would take a motor swapped vehicle on trade.

Motor swapping too, you are in the vehicle for the long run too. I see you never getting rid of it at that point. Same with deleting.

 

[grimmjeeper]

Without a doubt. Comparing like to like, of course. 5.3 to 5.7, 6.2 to 6.4, the Hemi drives so much better, and I don’t even own one. I have a Chevy.

 

[2nd 392]

The easiest performance swap will always be for the 6.4. The parts are all available from the factory and the fitment is exact. The 6.2 is not so bad either, it can be done within reason. LS swaps are not worth it at all, the Hemi is so much better it isn’t worth it. LS engines aren’t cheap like they used to be.

This- if you find a totaled 392, you have nearly everything you need -damage dependent- if not everything.
But still, good luck in CARB states.
this ain’t the old days when I found a wrecked C-2 Vette and just had to install the engine-trans and upgrade (everything) for function.

 

[mwilk012]

This- if you find a totaled 392, you have nearly everything you need -damage dependent- if not everything.
But still, good luck in CARB states.
this ain’t the old days when I found a wrecked C-2 Vette and just had to install the engine-trans and upgrade (everything) for function.

A little funny business with the VIN can solve that.

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