I did a search first and didnt come up with anything worht while so I thought i woudl post . . .

I just bought my first Jeep 3 days ago. Threw a rod driving it today and so I am thinking about getting rid of the 2.5L and going for the 4.0. I have a Cherokee withthe 4.0 and I like the motor.
My rig is a 1992 YJ with a 5 speed (I believe that means its a AX-15 tranny right?)
So, what is onvolved in doing the swap?

I assume the easiest donor woudl be a early to mid 90's Cherokee, right? Since they used the same tranny that shoudl bolt up right? What about the motor mounts, do I need to relocate them or build new ones all together?
What about wiring, is it difficult to mate up, or does it port straight across?

I think I can get what I need fiarly cheap so if its fairly painless I'll do it.

I just did some general searching on the internet, and it seems that if I want to do this I have to get EVERYTHING from a Cherokee to get this to work.
But I read that the Chevy 2.8 is a direct bolt up to my tranny. Has anyone done this?
I assume then that I wouldn't need to change anything other then the wiring harness & ECU thencorrect? ANyone have any write-ups or can provide some input?

if its a 4 banger it has the ax-5 only the 4.0 had the ax-15 so youll need a new trany also. i know a guy around my area did it once and he said if he would do the swap over he would go 350 with the amount of stuff you have to change its just as expensive ether way

ax-5 tranny. you have to change trannys and the input shaft on the t case. must switch harnesses grind of engine mounts and reweld them exhaust rad depending on donar clutch has to be delt with. there is more but this is just of the top of my head. you dont want the chevy 2.8 trust me.

A smallblock Chevy swap will cost you about the same as a 4.0L swap. Up to you.

Ben

In my humble newbie oppinion there is absolutlely no advantage in going from a 2.5 to the 2.8 Chev. In fact I'd rather have the 2.5 anyday, I beat the crap out of mine for six years and it's in another Jeep now still going strong. I know the 3.1 replacement from Chev is supposed to be better, but don't know enough about it to say if it would be worth it or not.

Fawk, just read you chucked a rod! If you go 4L then get the whole vehicle if you can, motor mounts are in different places.
A small block swap would be just as easy, if not easier, although it may depend more on your local smog laws which way you can go.

Depending on your circumstance, you might be better off, and save yourself a lot grief by putting in another 4cyl, then sell the jeep and buy the one you really want (engine wise). A lot of people will say this is the wussie way out, but the small incidentals will kill you during an engine swap, as far as time and money go.

David (in the middle of a 2.5- sbc swap)

I'll be doing this on the GF's TJ sooner or later. what I figured was:

4.0L Engine (complete, all accessories)
AX-15
NP231 (though, that should be the same as what she has now)
Computer
Wiring Harness

With all said items it should be a relatively simple swap. Yeah, some grinding and welding, but not a big deal if you have the tools for the job.

If I were you. I'de go hunting for a 92-99? wrangler thats been totalled and get the drivetrain out of it. $1700 for a totalled rig would still be cheap. (4.0L engine is $$$)

1st of all you have an ax5 tranny, which has the wrong input shaft and is a POS even behind a four banger.The t-case is a 21 spline input in the 4 banger and 23 on the 6cyl,so to use your tcase with a ax15 you will have to change the input.Basically ,the only somple way is to swap everything out,or just buy another 4banger.

I love my 2.5, hell, I even rebuilt it once, but if I was in your situation, first Jeep and all, I'd find a replacement 2.5L. If you're up to a custom job, find a GM 3800 V6, the GM 60 degree V6's have the same bellhousing pattern, and if you get a supercharged 3800, you'll be spanking 4.0L's left and right up until your AX-5 goes boom, then you swap in either a 700R4 auto and NP231 out of an S-10, or a SM420 with an S-10 2.8-T5 bellhousing and a Novak NP231 adapter

Originally posted by 4Bangler
I love my 2.5, hell, I even rebuilt it once, but if I was in your situation, first Jeep and all, I'd find a replacement 2.5L. If you're up to a custom job, find a GM 3800 V6, the GM 60 degree V6's have the same bellhousing pattern, and if you get a supercharged 3800, you'll be spanking 4.0L's left and right up until your AX-5 goes boom, then you swap in either a 700R4 auto and NP231 out of an S-10, or a SM420 with an S-10 2.8-T5 bellhousing and a Novak NP231 adapter

No WASTE OF TIME!! Do the whole swap at once, much easier and much more efficient that way.

Originally posted by twaldher

If I were you. I'de go hunting for a 92-99? wrangler thats been totalled and get the drivetrain out of it. $1700 for a totalled rig would still be cheap. (4.0L engine is $$$)

Well, your info is still a little wrong. For use in a YJ you are restricted to a '91-95 motor or the older Renix 4.0l in pre-'91 XJ's unless he wants a lot of extra work. The reason being is the fuel regulators on the '96 and newers are on the tank sending unit, not the fuel rail. I have yet to see a TJ motor fuel rail system adapted to a YJ tank, so most swap the sensors, harness and fuel system in from a '91-95.

For the work I would Go with a FI sbc.

Wait, are you telling me that a 2000+ motor won't swap into a 92 YJ? The dealership I bought the wrangler from said they put a 2000 TJ 2.5L into it. If what you are teling me is correct, they lied.

Sorry didn't mean to confuse you. I was talking only about the 4.0l engines.

I have no information on 2.5l swaps. I would figure the dealer only swaped a new bock and head into your Jeep and used the existing fuel system, wiring and sensors. That way they didn't have to deal with any wiring mismatches or the OBDII computer the comes in a 2000 TJ. Hope this was more clear.

I will bet the dealership did not put the 2000 electronics or smog into that 92.

Unless you put a V8 in, IMO its not worth the time, effort or cost to do a swap.

if you all you want is a 4.0L, sell your 4 banger and buy one with the 4.0.

if its 3 days old, you haven't done any mods to it yet so its just one stock jeep vs another stock jeep.

I was about to get real pissed, not that I am not already pised for them selling me a block that blew its motor within 3 days of buying it.
Anyway, thanks for all the info guys. I am still looking at options. I don't know if I can afford to do the 4.0 swap yuet, and all in al, I don't know if I woudl go that way. its a lot fo hassle to put it in, and if I have to swap in the tranny and ECU and everythign anyway, then I might as well look for what other blocks are good.
I actually like th enew FOrd 4.0 as well, and I had a good run with mine in my Ranger, so who knows.
Once again, thanks!

Hold on a minute here, you mentioned dealership in the same thread as throwing a rod within 3 days of purchase. There should be some way of bending the lemon laws to your advantage and get your damn money back so ya can look for another jeep that dosnt need a new engine. Look into it, a running rig beats one that you owe on that sits there begging for more money.

Well, I paid cash for it, so at least I dont owe a dime. I paid a good maoutn for it thoguh, bacsue I was put under the impression that she had a 2.5L with 20K original miles out of a 2000. Now, I am still starting tho think that they bullshitted me. I am going to grab the # off of the block and call into Jeep to find out what the motor is out of.
I really dont want my money back since the Jeep is cherry. I really want them to take the block and either replace it or rebuild it. I can put another in myself, as long as they get me another. I sold me daily driver, so now I no longer have a way to get to work! SO I nee dit taken care of quick.

As much as I hate to mention the scummy pimples on the collective ass of society (lawyers) one may be warrented in this case. Isn't there a 30 day warranty on used cars when sold by a dealer? If so have em fix it, or you'll have a slimey (lawyer) friend contact them. Dont front the money for an engine swap on a 3 day old to you vehicle.