KJ diesel in an XJ?

[casm]

Out of curiosity: has anyone looked into the feasibility of dropping the upcoming turbodiesel out of a KJ into an XJ? I'm assuming we're going to get the same unit used in the European KJs, so I'd guess that someone there may have already tried this. I am a fan of diesel, having had a pair of diesel Land-Rovers and indestructible Peugeots.

Given the price of gas and fact that I drive a high annual mileage (22,000 and up), I'd be willing to sacrifice 3-4 seconds to 60mph for close to 30mpg. DMV issues aside (I've heard that in California you can convert a diesel to gas power, but not vice-versa - still have to confirm this, though), does this sound doable? I plan on keeping my XJ until it's utterly destroyed, so amortising the cost of the conversion over the lifetime of the vehicle makes financial sense.

Anyone have any input on this? I'm really interested in the idea.

[Darky]

I don't know anything about ti being possible, but with diesels today, you won't necessarily be losing any power. Some (Mercedes C Class comes to mind) are actually faster than their gas counterparts. And even though if I remember the numbers correctly, the KJ diesel has less power than the 4.0, its a turbo, turbos are easy to add power to. Intercooler, bigger turbo, different pullies, etc.

[ryurabbit]

Diesel KJ's are not out yet to the best of my knowledge and smog being what it is I am not sure if they will be retrogradeable to an XJ simply because of the fuel pressures of the common rail injection. They dont want us tinkering with a 7000psi fuel rail!

Out of curiosity: has anyone looked into the feasibility of dropping the upcoming turbodiesel out of a KJ into an XJ? I'm assuming we're going to get the same unit used in the European KJs, so I'd guess that someone there may have already tried this. I am a fan of diesel, having had a pair of diesel Land-Rovers and indestructible Peugeots.

Given the price of gas and fact that I drive a high annual mileage (22,000 and up), I'd be willing to sacrifice 3-4 seconds to 60mph for close to 30mpg. DMV issues aside (I've heard that in California you can convert a diesel to gas power, but not vice-versa - still have to confirm this, though), does this sound doable? I plan on keeping my XJ until it's utterly destroyed, so amortising the cost of the conversion over the lifetime of the vehicle makes financial sense.

Anyone have any input on this? I'm really interested in the idea.

[Dr. Dyno]

Given the price of gas and fact that I drive a high annual mileage (22,000 and up), I'd be willing to sacrifice 3-4 seconds to 60mph for close to 30mpg. ........I plan on keeping my XJ until it's utterly destroyed, so amortising the cost of the conversion over the lifetime of the vehicle makes financial sense.

You could think about converting your 4.0 to run on LPG as well as on regular gasoline. Performance and fuel economy are similar with both fuels but LPG is far cheaper and cleaner burning than gas.

[casm]

You could think about converting your 4.0 to run on LPG as well as on regular gasoline. Performance and fuel economy are similar with both fuels but LPG is far cheaper and cleaner burning than gas.

Understood, and I've found quite a bit of info on how this has worked out for people in (mainly) the UK. Apparently the I6 is a good candidate for LPG, but my concerns are fuel availability and the need for a secondary tank unless I go completely to LPG - again, though, fuel availability would be enough to put me off that idea, and I don't want to lose load space with a second tank.

I've been doing a bit of poking into the KJ diesel idea - what mainly attracted me to it in the first place was the potential for torque gains in addition to better MPG, plus parts & service availability if anything did happen. I think it is doable (with the fabrication of custom engine mounts), but can't find information on whether or not it'll mate up to the transmission in the XJ. Again, I suspect it will but can't find a direct comparison of KJ and XJ tranny patterns anywhere.

[Lawn Cher']

Whatever tranny the KJ uses behind the diesel would have to bolt up to the XJ transfer cases since they are a carryover, so you could consider swapping the engine & transmission together. I've been pondering the same thing that you propose here for my wife's '01 XJ, just waiting for the release of the KJ diesel for further proof of concept.

[John90XJ]

:flame: Let the flame war begin but wouldn't a solid axle swap into a diesel KJ be easier? :flame:

[Yucca-Man]

Maybe easier, but you'd still be driving a Diesel Kia...with a solid front axle. Reminds me somehow of polishing a turd...

[casm]

Let the flame war begin but wouldn't a solid axle swap into a diesel KJ be easier?

To be honest... I really don't want a KJ. I went out and drove one last weekend to see if I liked it, and evaluate its potential as an eventual XJ replacement. While it basically drove OK, it feels more like a car than a Jeep, and the front suspension leaves me suspicious as to its off-road ability (at least, without major work). Ultimately, while I feel fairly confident in my XJ's ability to get me out of most things I might get ito, the Liberty didn't impart that level of confidence.

Not to reiterate sentiment that I'm sure has already been aired, but I got the impression that Jeep pandered to the people who complained that the Cherokee wasn't carlike enough for them in designing the Liberty. Had they put live axles under it front and rear to begin with, I'd feel a lot better about its potential, but now I just see it as a possible parts source for a diesel engine.

[John90XJ]

I can see what you mean...they just aren't all that attractive to me either. But sourcing a diesel motor and it's required peripheral equipment would certainly be more of a project than finding an axle.

And since this is presently an exercise in "what ifs", I suppose it really matters not what way you decide to go today.

Wouldn't finding a Euro-spec diesel, from an XJ, be a worthy option? Given the ability to enhance performance in one, is it not a good candiate?

[casm]

I can see what you mean...they just aren't all that attractive to me either. But sourcing a diesel motor and it's required peripheral equipment would certainly be more of a project than finding an axle.

Agreed. Only thing is, I have no idea how major a project slipping a live axle under a KJ would be. My suspicion is that it would be a lot of work, and probably ultimately involve grafting most of the front suspension from an XJ on there somehow. Whether or not that's more work that doing the engine swap I'm proposing is another matter, but I don't see one necessarily being easier than the other.

Wouldn't finding a Euro-spec diesel, from an XJ, be a worthy option? Given the ability to enhance performance in one, is it not a good candiate?

Well... The short answer is 'yes', and I did actually consider this as a possibility. However, the slightly longer answer is that it might be more difficult due to legislation than doing the KJ diesel swap - remember that the KJ will have a federalised engine, but that none of the European turbodiesels (I wouldn't bother with the naturally-aspirated ones) were ever type-approved for use in the US.

This could become a major problem when you visit the DMV to inform them of your swap, and potentially lead to a 'fit an approved engine or destroy the vehicle' order - and having been through something similar with them once already, I have no desire to repeat the experience. I really, Really, REALLY hate the California DMV.

One other thing to consider is that if the transmission will bolt right up to the transfer case, it'd be nice to have the 5-speed auto :) Also, KJ diesels do appear to have the same type of modchips available for them as the XJ diesels did, so the aftermarket is there for performance bits.

[John90XJ]

I really, Really, REALLY hate the California DMV.

'nuff said about that....I feel your pain. I've heard nothing good about the California DMV.

[SVT]

Skip the KJ Diesel & put a cummins in, put some D60 's underneath & figure out what AA would have that a guy could bolt up to the Cummins. Even if a guy could get the new Turbo Dodge engine with their fuel manegment system & then get a chip , you would have gobs of power (to much to know what to with) & awsome fuel milage. Thats this :canada: farmers 2 cents ( which is like negative cash in America) ;)

[SVT]

:wstupid:
Ya I was just looking at a hummin C & there is no way it could even fit in a Xj unless you modified fire wall & you would need 8" springs in front just to have 3" of lift, yes I am on Crack & it's good want some ? :anon:

[OILBURNER]

Biggest issue I see w/ a Libby diesel swap would be the electronics. Modern diesels are computer controlled so you'd have to do a lot of rewiring. But the same thought has crossed my mind = TD XJ would be sweet.

Not like the old ones - I have a VW diesel in a Samurai, and it only needed 1 wire for it to run, & that was to the starter! LOL

[casm]

Biggest issue I see w/ a Libby diesel swap would be the electronics. Modern diesels are computer controlled so you'd have to do a lot of rewiring. But the same thought has crossed my mind = TD XJ would be sweet.

Yep. I really wish that using the Euro-spec TD was a more doable option, seeing as how the ECU, wiring, etc. are all (relatively) drop-in items. Unfortunately, it doesn't look as though Haynes did a manual for the diesels. Bleh. Oh well, looks like I'll be keeping an eye out for a totalled KJ TD.

Incidentally, I have a call in to a DMV referee to see if she can't dig anything concrete up re: the legality of a gas -> diesel conversion in CA. Still waiting for word back from her.

[BlueGerbil]

Don´t even think about a swap of an "european" diesel from a XJ into a 4.0 ! :twak:

The 2.5l motors produced by VM (an italian company) are known for their thermal problems and problems with the head. And the newer 2.7/2.8l CDI motors from Mercedes weren´t available in the XJ.

There is the possibility to modify the motor to 142 PS (http://www.upsolute.com/), a friend of mine did this and that didn´t add any relialibility either! He has done much to improve the cooling of his XJ (including a custommade 6 core radiator, see below), but I don´t think, it´s the way to go...
http://www.gaisch.at/CherokeeAustria/xjeep2/cooling/IMG_0007.jpg

[casm]

Don´t even think about a swap of an "european" diesel from a XJ into a 4.0 ! :twak:

Uh, you might want to go back and check my earlier comments :) I'm waiting for the federalised version before even considering it. I remember the early XJ diesels (I'm half-Irish, grew up there, and bought my XJ largely because I remembered them fondly from when they came out in about 1993 in RHD), and they were possibly as mediocre as the US-spec Renault TD from the '80s.

The 2.5l motors produced by VM (an italian company) are known for their thermal problems and problems with the head. And the newer 2.7/2.8l CDI motors from Mercedes weren´t available in the XJ.

Right, hence why I'm waiting for a totalled US-spec diesel KJ to pop up ;)

With a 50% increase in fuel prices since February, diesel's looking very attractive around here - especially since it would mean upping the torque figure at the same time, as well as being smog-exempt.

[BrettM]

i had a roommate last year who worked at the company that designed the fan for the diesel KJ (in Jackson MI). they had a fully operational Diesel KJ, he said it was pretty sweet, but i never saw it.

[ZmOz]

You could think about converting your 4.0 to run on LPG as well as on regular gasoline. Performance and fuel economy are similar with both fuels but LPG is far cheaper and cleaner burning than gas.

Not in the U.S. Propane is about $1.85 here, while gas is about $2. Given the fact that you need more propane to go the same distance as gas, it will actually cost quite a bit more per mile.

[casm]

Not in the U.S. Propane is about $1.85 here, while gas is about $2. Given the fact that you need more propane to go the same distance as gas, it will actually cost quite a bit more per mile.

$2/gallon? Sign me up for that: in L.A. we're being hit for around $2.30/gallon for 87 where I am (though I have seen it as low as $2.15/gallon - prices do seem to be slowly coming down). Diesel's down around $1.90-$1.95, so there's a pretty decent difference between the two.

Also, as an aside for anyone who doesn't know about it yet: www.gaspricewatch.com - locate the cheapest stations in your area.

[Mikel]

I've heard of a couple of Cummins 4BT (3.9L, 4cyl) swaps into XJ's, that get close to 35MPG on the highway.

4BT's in marine applications are rated to 250HP, but that would probably shake an XJ to death :D

[Mikel]

http://turbodieselregister.com/forums/showthread.php?threadid=95320&highlight=cherokee+4BT

[burntkat]

:flame: Let the flame war begin but wouldn't a solid axle swap into a diesel KJ be easier? :flame:

may well be.

Know anyone giving away KJs?

[basalt51]

It may have already been mentioned but...The Diesel won't be available in CA. So I doubt you'll be able to swap it in. CA sucks.

[ZmOz]

$2/gallon? Sign me up for that: in L.A. we're being hit for around $2.30/gallon for 87 where I am (though I have seen it as low as $2.15/gallon - prices do seem to be slowly coming down). Diesel's down around $1.90-$1.95, so there's a pretty decent difference between the two.

Also, as an aside for anyone who doesn't know about it yet: www.gaspricewatch.com - locate the cheapest stations in your area.


Just a couple weeks ago I filled up for $2.49 here. Now most places are around $2.05-2.15. I about crapped myself the other day when I saw Costco selling gas for $1.86! The 76 just across the street was still $2.25...

[Cherokee91Red]

Glad I don't live in Cali. If the gas is over 1.85 I think thats expensive. Just say 1.76 last night.

[JohnnysXJ]

Yucca is right...the KJ is IMHO way too kia-ish....but DC is big into the "minivan-as-a-sportutility" concept these days (hemi or not, the new durango is an abomination), so thats what you get out of em. The folks from Car-and-Driver (note the mag's first name) complained incessantly about the XJ so DC obliged and went IFS with the KJ and <groan> the WJ's replacement. IRS couldn't be too far behind...Ford will see to that. soon you will be able to go down to your Jeep dealer and buy a shiny new Jeep Grand Voyager...with a deisel. Not that I'm bitter or anything.

[scoobyxj]

Glad I don't live in Cali. If the gas is over 1.85 I think thats expensive. Just say 1.76 last night.




1.69 in ohio still to f------ expensive!!!!!!!!!!!!!!!!

[casm]

Just a couple weeks ago I filled up for $2.49 here. Now most places are around $2.05-2.15. I about crapped myself the other day when I saw Costco selling gas for $1.86! The 76 just across the street was still $2.25...

You'll hate this (http://www.speakeasy.org/~casm/cimagasprices.jpg), then. It was taken last weekend at the last-chance gas station off of I-15 north at Cima Road. Desert price gouging has always been bad, but this is by far the worst I've ever seen it.