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I've seen a bunch of conversions with CJ's, YJ's and TJ's, but I haven't seen anyone put a 4BT in an XJ (older square style small Cherokee).

Has anyone out there done one or better yet doing one with pictures to see?

Thanks. I was thinking of a full size Chevy Blazer, but there are several nice litttle XJ's floating around that would make a good swap (If the motor fits, that is).
 

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The problem with the xj they don't have a frame (body is the frame) Anything can be done with time and money .Now if your talking about the jeep waggie that would be a better choice.

Scott
 

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The problem with the xj they don't have a frame (body is the frame) Anything can be done with time and money .Now if your talking about the jeep waggie that would be a better choice.

Scott
you know, I don't really get this whole "it doesn't have a frame, it's like tissue paper" mentality.

Any of you ever take an engineering class?

At the very worst-- it's a little channel and some welding time. However, that's overkill. Keep the engine mild and the XJ is a fine platform, frame or no.

(the simple fact of the matter is-- unibody vehicles are MORE torsionally rigid than simple ladder frames-- and it's torsional rigidity that concerns us)

Other poster who said "totally doable" and posted the pic- DETAILS, man! Details!!

I have a 90 X and have been planning a swap. Have it all figured out I am pretty sure, just haven't had the $$$ to purchase the engine yet.
 

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I also think these platforms are very sturdy as long as rust hasn't got a hold of them. When I did the conversion I found no need to weld anything to the frame. The original motor mounts bolted the main part of the frame in about 6places over an area of about 5 * 8 inches, which I felt was quite adequate so I reused them.

The support the frame strength I got into a small head on collision with a 3/4 ton ford and bent the frame on it, and my vehical had no damage that I could tell other then the bumber tilting slightly.
 

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speaking of motor mounts-- what did you do for them?

more pics, particularly of motor mounts, would be greatly appreciated!
 

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you know, I don't really get this whole "it doesn't have a frame, it's like tissue paper" mentality.

Any of you ever take an engineering class?

At the very worst-- it's a little channel and some welding time. However, that's overkill. Keep the engine mild and the XJ is a fine platform, frame or no.

(the simple fact of the matter is-- unibody vehicles are MORE torsionally rigid than simple ladder frames-- and it's torsional rigidity that concerns us)

Other poster who said "totally doable" and posted the pic- DETAILS, man! Details!!

I have a 90 X and have been planning a swap. Have it all figured out I am pretty sure, just haven't had the $$$ to purchase the engine yet.

1. Not to be a jerk but if you know everything than why did you ask !
2. I never said it couldn't be done,I just said tha fact's that there was no frame.
3. Your quesstion was very general like you didn't have a clue where to start!
4. no hard feelings here !!!
 

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The mounts consisted of some 5" channel and some heavy flatbar across for added stiffness. The assembly was mounted to the orignal points on the frame using part of the the original motor mount brackets. I am not good on the explanation but the picture will help. I used ford flat style mounts and have no vibration problems and the best part, those mounts are about 10 dollars a piece and very easy to get.
 

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1. Not to be a jerk but if you know everything than why did you ask !
2. I never said it couldn't be done,I just said tha fact's that there was no frame.
3. Your quesstion was very general like you didn't have a clue where to start!
4. no hard feelings here !!!
1) At that point I hadn't even posted in this thread. So how does this apply?

2) Didn't say you said it couldn't be done. but like many, you said "the problem with the xj is it doesn't have a frame". Well, it's not a problem.

3) See number 1, above. I hadn't at that point even posted, let alone asked a question. so what are you referring to?

4) none here. Give my love to the wife and kids. :)
 

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1) At that point I hadn't even posted in this thread. So how does this apply?

2) Didn't say you said it couldn't be done. but like many, you said "the problem with the xj is it doesn't have a frame". Well, it's not a problem.

3) See number 1, above. I hadn't at that point even posted, let alone asked a question. so what are you referring to?

4) none here. Give my love to the wife and kids. :)
Sorry for that I was talking and posing at the same time,:smile:
 

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Sorry for that I was talking and posing at the same time,:smile:
not a problem sir. Good to meet ya :)

see, that's what's cool about this board. It could have went the way of Pirate4X4 right there, instead it's two guys basically ragging each other, then tossing a fresh beer at the other guy with a grin and a muttered "dumbarse" :)
 

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now- Jeepcummins-- you REALLY need to post more, man. I've got a 90 XJ that's just begging to go diesel. The transmission is leaking like crazy, I have a 700R4 in the shed just itching for a rebuild, and the motor is basically shot. So it's either put a rebuilt 4.0 fuel hog (I dislike this motor, and dislike having to buy $3 gasoline even more), or go diesel and run WVO.

I know which way I wanna go. Now the only question is, how to get there. I'm looking at the 4BT as well as GM 5.7 diesels (yes, I know the old wives' tales about that engine- sorry, they're wrong- -and I can get 'em dirt cheap)

will likely build it with the GM diesel to get it running on WVO, then keep my eyes open for a 4BT.
 

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Ever wheeled an XJ for long? They break.

Have fun with those 5.7's MOOOAHAHAHAHAH

:beer:
 

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Ever wheeled an XJ for long? They break.

If abused enough, everything will break :tongue:

Some simple upgrades make them pretty solid up to 35" tires, and they will easily outflex an IFS tacoma beer

Yes i have personal experience with this stuff, I wheel a ZJ (Grand Cherokee) on 35's.

I'm not sure why you hate 4.0's. I've had good luck with mine, and so have many others. Mine is underpowered, but that can be fixed. i'm going to swap in a 360/46RE, but only because they came in my Durango. Otherwise i had plans to stroke it to 4.6 and put in an AW4.

When it comes to Unibody's they can take some abuse, but when they're done they're done, gotta start over, at least that's the easiest route most of the time. With a frame, if it goes you can either buy a new one or build a new one without replacing the body. Good news in this area for XJ's is one with a decent body is readily available and dirt cheap.

Personally i think that a 4BT is a lot for an XJ. If you want a unibody Jeep, a better choice, in my eyes, would be a ZJ. The XJ's were the first AMC vehicles to be computer designed, also the first unibodies. There were a lot of advancements in design from when the first XJ's were designed to when the ZJ was designed, the ZJ unibodies are a lot heavier and stronger than XJ's. Personally I'd still rather have a frame.

Can it be done? well that's already been answered. Will it hold up in the long run? if done right and not abused, probably.

I know you already have the XJ so it's an easy platform to choose. It also depends on what you want it for. If it's a weekend warrior/DD then it will probably do the trick. If you think you want to tow things somewhat heavy, you might want to consider something stronger and with a longer wheelbase. This is how I ended up in a Durango. A solid front axle is pretty much a must in order to have 4wd, but That's not a terribly hard/expsnsive operation either.

When it comes to money, it's not a cheap swap. It's definately cheaper to stroke the 4.0 that's in there now than to put a 4BT in. Unless a 4bt falls into your lap, then it still might not be cheaper. Will you save it all in fuel prices? maybe, but it will probably take a while. reports on mileage of a stroked 4.0 are pretty decent from what i've seen.

Sorry if this is a lot of rambling, hopefully something decent came out of it all.
 

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We have been doing alot of stuff with some Cherokee's latly, and I tell everyone of my customers the first thing they should do is add a set of these
http://www.tntcustoms.com/webv5/xjstiffeners.asp
This way you can weld all over them for your rails, or suspension links, or whatever. They fit great, and work great as far as I can tell. I havnt had any frame rails ripping apart since we started using them.
 

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We have been doing alot of stuff with some Cherokee's latly, and I tell everyone of my customers the first thing they should do is add a set of these
http://www.tntcustoms.com/webv5/xjstiffeners.asp
This way you can weld all over them for your rails, or suspension links, or whatever. They fit great, and work great as far as I can tell. I havnt had any frame rails ripping apart since we started using them.
TNT makes some pretty awesome products.

I did a similar thing with my zj when i went to a long arm style of suspension. I took 4x6x1/4 box tubing and cut it in half. stitched it to the unibody every couple of inches and plugwelded it as well. It's held up so far though i've only make it to the trails once since i put it on.
 

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-I'm not sure why you hate 4.0's. I've had good luck with mine, and so have many others. Mine is underpowered, but that can be fixed. i'm going to swap in a 360/46RE, but only because they came in my Durango. Otherwise i had plans to stroke it to 4.6 and put in an AW4.

-Personally i think that a 4BT is a lot for an XJ. If you want a unibody Jeep, a better choice, in my eyes, would be a ZJ. The XJ's were the first AMC vehicles to be computer designed, also the first unibodies. There were a lot of advancements in design from when the first XJ's were designed to when the ZJ was designed, the ZJ unibodies are a lot heavier and stronger than XJ's. Personally I'd still rather have a frame.

- know you already have the XJ so it's an easy platform to choose. It also depends on what you want it for. If it's a weekend warrior/DD then it will probably do the trick. If you think you want to tow things somewhat heavy, you might want to consider something stronger and with a longer wheelbase. This is how I ended up in a Durango. A solid front axle is pretty much a must in order to have 4wd, but That's not a terribly hard/expsnsive operation either.

-When it comes to money, it's not a cheap swap. It's definately cheaper to stroke the 4.0 that's in there now than to put a 4BT in. Unless a 4bt falls into your lap, then it still might not be cheaper. Will you save it all in fuel prices? maybe, but it will probably take a while. reports on mileage of a stroked 4.0 are pretty decent from what i've seen.

Sorry if this is a lot of rambling, hopefully something decent came out of it all.

First off-- I hate the 4.0 because it's a closed-source ECU. With my GM products, I can easily read the data in realtime via my laptop. That, coupled with the fact the garages I've paid to do a diagnostic are bullshit artists, and I think you see where I'm going. I do ALL my own work.

I agree about rather have a frame for the reasons you mention. But this XJ was pretty much free. I'd rather have a framed Jeep, but then security comes into play owing to the soft top. Yes, hardtops are available, and then there's the SJ series (too big). But I already have the XJ.

Towing will be done with my S-10 Blazer once it gets upgraded brakes by way of hydroboost. I know you'll say this is not optimum either-- but lots of folks tow with ZJs and the like. I'll never be towing anything heavier than what I've seen towed with ZJs.

- the swap wil lpay for itself quite quickly. You can't run WVO in a gas engine. I will in a diesel.
 

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We have been doing alot of stuff with some Cherokee's latly, and I tell everyone of my customers the first thing they should do is add a set of these
http://www.tntcustoms.com/webv5/xjstiffeners.asp
This way you can weld all over them for your rails, or suspension links, or whatever. They fit great, and work great as far as I can tell. I havnt had any frame rails ripping apart since we started using them.

Did the same thing with $30 worth of channel.
 

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as far as security with an open top Jeep, the cage you'd be dumb not to put in is way stronger than the Cherokee roof.

I had a nice little lifted XJ, flexed fine, drove ok, but made me very nervous due to the "frame" issues, and the more important problem: hardly any crush room between the door and my body.
The 4-5 I've seen rolled (and not that bad a roll for any of them) just made me nervous.


But! I believe in cages and it colors my expectations of safety. I also only own fullsize GM's right now, and they are all bigger than 85% of the vehicles I am on the road with at any given time. So I may be delusional as well.

XJ's are fine vehicles, not sure I'd overburden them with a Cummins though.
 

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since when does a rollcage have anything to do with security?

give me a soft top jeep, and in 20 seconds everythng of value will be mine- were I so inclined.

I'll take the dubious security of a metal roof and a locked door over a fabric roof and my Kershaw, any day.
 
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