Liberty to YJ 2.8L diesel swap. Possible? Economically viable?

Sine Deviance

Sine Deviance

New member
Hi all. I sense that my engine is on it's way out and won't last much longer. Maybe a year, maybe less. I have the 2.5L now and I was already getting really tired of 16mpg and a top speed of 65mph. If it's gonna die, I'm gonna consider swaps first.

I'm really interested in a possible 2.8L diesel swap from a donor Liberty. Does anyone know any specifics on such a swap? Or if it's even possible? From what I've read, the AX-15 and NV3500 will both bolt right up to the 2.8L without any adapters. The engine would also fit nicely into the YJ's bay. It should also be emissions-legal for the new '05 laws. I'd have to get a stronger trans and axles but I would have to do that no matter which swap option I pick. I have no idea how the wiring would be done but I'm sure I could figure out a solution.

With that in consideration, for fuel economy, would it be a good swap option? What kind of MPG do you think I could get with such a swap? And do you think it would be easier or harder, cheaper or more expensive, than a swap to a Gen II or Gen III Chevy smallblock?

Or, do you think I should just sell the Jeep now and get something else? :lol: For what it's worth, it is a Rio Grande edition and I'd kinda like to hold onto it if it's worth holding on to.

Thanks for any opinions you guys might have :D
 

I'd guess the best mileage you're gonna see is the similar to what the diesel Libby is rated for.
 
That would be a cool swap. The only issue i could think of is the PCM. It's a hybrid communication meaning, part Can bus and part PCI communications. If you could find a generic PCM to run on that engine, it would be better than trying to retrofit the wrangler with the other ECU's the original PCM requires.
 
Before you get too involved, you need to consider the legality for the swap in your state.

In my state (ass-achusetts) you can not swap an diesel engine into a vehicle that was not offered with a diesel engine, ex. YJ's never were offered with a diesel, so I can not legally register, but a same year xj, the swap is legal since the xj's were offered with a diesel.

Also, check with your emmisions laws, that 2.8 uses a system similar to ODBII diagnostic (I think they actually use the same name) thats a lot of sensors and computers to swap over.

a 4bt might be a better option, well documented, same milage, more power, no electronics to swap, just ahot to the battery and the starter, add a ground and pretty much done.

Good luck, I would like to see it done!
 

Thanks for all the input so far.

Bounty__Hunter said:
I'd guess the best mileage you're gonna see is the similar to what the diesel Libby is rated for.
Click to expand...

Ahh. I was kind of afraid of that. According to some stuff I've been reading, the Liberty CRD gets about 20-25 actual MPG (people say that the overhead MPG counter in the Liberty CRD is very inaccurate and regularly reports 5 MPG more than actual.) 20-25 mpg seems pretty damn bad for a 4-cyl variable-geometry turbodiesel.

I was really shooting for 25-30mpg, or even better. That's probably just a pipedream though, and I could certainly live with 25 mpg.

SteelHeadz said:
That would be a cool swap. The only issue i could think of is the PCM. It's a hybrid communication meaning, part Can bus and part PCI communications. If you could find a generic PCM to run on that engine, it would be better than trying to retrofit the wrangler with the other ECU's the original PCM requires.
Click to expand...

I also think it would be a cool swap, and the 2.8L seems to be pretty capable albeit being factory option in a mall-crawler like the Liberty (seriously, when the hell is Jeep going to wake up and realize that Wranglers need a diesel option?)

I wasn't aware of how the 2.8L PCM system worked so I may reconsider based on that alone. I don't want to have to jump through tons of hoops to make my stock gauges play nice with a newer PCM. That's like finding rooster teeth.

jps4jeep said:
Before you get too involved, you need to consider the legality for the swap in your state.

In my state (ass-achusetts) you can not swap an diesel engine into a vehicle that was not offered with a diesel engine, ex. YJ's never were offered with a diesel, so I can not legally register, but a same year xj, the swap is legal since the xj's were offered with a diesel.

Also, check with your emmisions laws, that 2.8 uses a system similar to ODBII diagnostic (I think they actually use the same name) thats a lot of sensors and computers to swap over.

a 4bt might be a better option, well documented, same milage, more power, no electronics to swap, just ahot to the battery and the starter, add a ground and pretty much done.

Good luck, I would like to see it done!
Click to expand...

I live in North Carolina, and as far as I can tell, I can swap in whatever I want so long as it was offered factory in a light truck. I think it also needs to be same year or newer. I will make sure to clarify this before collecting any parts.

Dunno if that means the 4BT is out, what years did Cummins offer those? I know they were offered in some light trucks. The only thing currently keeping me from jumping on the 4BT bandwagon (besides not knowing much about it's legality) is the price; it seems like no matter where I look I can't find one for less than $4000, and even those need a rebuild before they'd be worth swapping. That's way more than I want to pay. I found a low-mileage 2.8L VGT in a junkyard in Texas for $2200. That's still a bit steep to me considering I could probably pull a Chevy smallblock/4L60E combo locally for $1000 or less, but I am coming to terms with the idea that diesel is a more expensive swap option.

If you guys were in my position and had a budget of around $3000 (maybe an extra grand if absolutely necessary) to play with, what would you do? I don't HAVE to go the diesel route, it just seems like the best way to go for a good balance of MPG and torque. Note that my budget of around $3000 is just for the engine, trans, custom driveline, and any adapters I'd need to make it work. I can set aside some extra cash for a Ford 8.8 or D44 rear and stronger front suspension.

(Please don't recommend an AMC 4.0L swap because I just don't think it's worth the time/money/effort. I could go to something much more powerful i.e. Chevy smallblock for less money and time invested.)

Thanks again :D
 
Last edited:
the 4bt is still being producted new and is equipt in a variety of applications including box vans and generators. The best source for a 4bt is to find a old bread van or a chevy vandora cube truck (same thing) I have seen them rotted out on the side of the road for sale for under a grand, running and drivable. the bodys on most were not made from galvinized steel so they rotted out. the ones that are catching a higer price are simplay because the bodys were made from aluminum.
 
Small block chevy is always fun. Get a vortec from 96 up and you will get wicked mileage plus the power to put a smile on anyone short of john forces face. Easy swap wirings a breeze and no need to worry about can bus systems all wires can be spliced in to factory pdc.
 

Jester32 said:
Small block chevy is always fun. Get a vortec from 96 up and you will get wicked mileage plus the power to put a smile on anyone short of john forces face. Easy swap wirings a breeze and no need to worry about can bus systems all wires can be spliced in to factory pdc.
Click to expand...

Well, after poking around and reading lots of diesel swap info, I really don't think it's a good idea right now. With all the trouble I would probably have with it I'd rather just rebuild my AMC150 and slap a turbo on it. A 5.7L Vortec sounds pretty good to me, actually. 'Easy' is always good and I do have some experience with older (i.e. carb'd) smallblocks. What kind of MPG are we talking about, do you think?

25mpg with a light foot would be pretty awesome.

Also, as awesome as the 700R4/4L60E are, I really want to stick with a manual trans. What manual trans would you reco' for a 350 Vortec swap? I am thinking BW T19 for strength and reliability, but I really want a 5-speed.

Thanks!
 
Last edited:
I would go for a nv 4500. They came in every make of veh. Got a great low first and a nice over drive. You just have to be careful on length but this swap is very common. You want the engine as far forward as possible. You might even be able to find a gm 231 to bolt to it with left hand drop as long as the t case is clocked proper. Novak has a bunch of info on it to. Im getting my rad for my small block into my xj from them. You could probably get 25 with the five speed trans easy those vortecs were suprisingly good on fuel.
 
You can also keep the ax-15 its a strong. Light trans its a contender to because it came in the yjs.
 
Jester32 said:
I would go for a nv 4500. They came in every make of veh. Got a great low first and a nice over drive. You just have to be careful on length but this swap is very common. You want the engine as far forward as possible. You might even be able to find a gm 231 to bolt to it with left hand drop as long as the t case is clocked proper. Novak has a bunch of info on it to. Im getting my rad for my small block into my xj from them. You could probably get 25 with the five speed trans easy those vortecs were suprisingly good on fuel.
Click to expand...

Sounds good :D I will start looking around for NV4500's. I think I would stick with the stock NP321-J that I have, though; I don't want to get into changing the ratio on a tcase.

Jester32 said:
You can also keep the ax-15 its a strong. Light trans its a contender to because it came in the yjs.
Click to expand...

Jester32 said:
That would be my choice for simplicity. Www.novak-adapt.com/knowledge/yj_87_95_swap.htm
Lots of info there.
Click to expand...

But I don't have an AX-15. I have an AX-5, and they are pretty weak. I'm running the 4-banger, remember? :D

EDIT: Found this:

http://www.smartpartsauto.com/manual_transmission_nv4500_dodge.html

Price seems pretty damn good, almost too good. Anyone know about this site?
 
Last edited:
Right on. I been doing some research and the only j case that is a super easy swap is dana 300 to mate to the nv 4500. An ax15 might be a more budget friendly swap if you can find one.
 

Sine Deviance said:
Ahh. I was kind of afraid of that. According to some stuff I've been reading, the Liberty CRD gets about 20-25 actual MPG (people say that the overhead MPG counter in the Liberty CRD is very inaccurate and regularly reports 5 MPG more than actual.) 20-25 mpg seems pretty damn bad for a 4-cyl variable-geometry turbodiesel.
Click to expand...

I dont know why most people in the US think just because you got a diesel, you will get a gazzillion miles per galon; we run lots of diesels around Latin America, and it's ussually between 20 and 30, and on a YJ (with its brick-like aerodynamic characteristics), I would guess closer to 20 than 30...

I also think there are better options out there than the Jeep TD engine (and even the 4BT). Toyota and VW have some good engines out there you may want to consider. Actaully, there is even a kit to use the small VW diesel engine in the Jeep, if that's your type of stuff...
 
jfrabat said:
Toyota and VW have some good engines out there you may want to consider. Actaully, there is even a kit to use the small VW diesel engine in the Jeep, if that's your type of stuff...
Click to expand...

Maybe, but they wouldn't have any power. That's why I wanted to go with the 2.8L or the 4BT, so I could have some extra power when I want it.

I think the 5.7L Vortec is the best option so far.
 
Sine Deviance said:
Maybe, but they wouldn't have any power. That's why I wanted to go with the 2.8L or the 4BT, so I could have some extra power when I want it.

I think the 5.7L Vortec is the best option so far.
Click to expand...

Hmm... I dont agree with this.

My Toyota Fortuner with the 1KD-FTV engine with D-4D technology puts out 253 lb·ft of torque, and does that all the way between 1400 and 3200 RPMs.

Think about it; the 4.0L makes what? 224 lb·ft IIRC... And that was at higher RPM's, which really you rarely used when wheeling (except in mud and sand).

Felipe
 

Vortec would have that fun factor to. Nothin sounds better than a sbc above 3000 rpm. It would be a head turner. Im goin with a 383 in my cherokee. Just tryin to blow up the 4.0l. A little nitrous should do the trick. And by little i mean alot.
 

Thats all you really need. They are strong right outta the box
 
You must log in or register to reply here.

Similar threads

M
RPM dips/engine stalls at idle (intermittent), 99 4.0
2 3 4
Replies
61
Views
6K
Mercury
M
TerryMason
Would an extractor work to change the fluid in my automatic transmission
Replies
14
Views
13K
TerryMason
TerryMason
TerryMason
Time for another water pump
Replies
10
Views
850
JPNinPA
JPNinPA
M
Random Misfire, No Codes
Replies
11
Views
833
Mercury
M
TerryMason
Lube your zippers!
Replies
5
Views
6K
wrbrd
wrbrd
Back
Top