4.0L swap: What am I in for?

GaryMB

New member
RE: Fire up the BBQ grill !!!

Well it looks like i may be doing more than a simple transmission swap this summer. The trusty 258 is burning alot of oil, and it may be time to retire her to craigslist. I'm thinking of swapping in an nv3550 and 4.0L. So...what am I in for? I read some writeups a while back, but just to refresh me, how would you describe the whole experience? Is it something I could do in a week or so, before my big rubicon trip? Also, is the stroker a good idea if it will only be backed by an nv3550?
 

RE: sensor

I did the same thing (kinda) put a 98 4.0L/ 01 tf 999 in a 87 YJ. The hardest thing is the computer. Had a buddy how is a mechanic do that. sorry..Everything else is bolt in. You might have to fab a transmission mount, new drivelines, some other minor things. You'll love the FI, and the response of the 4.0L. Plus it is cheaper than the stroker kits, just find a low milage(under 50k)Get everything from the donor too.
 
I've been searching for a strong running 4.0L for a while now...so far nothing. Right now Pick N Pull is having a sale--engines are $80 and trannies are $43. I think I'll try to get an engine and transmission tomarrow and just plan on rebuilding them. Won't I have to worry about the crank position sensor and fuel pump, though? Also, I've always been curious about strokers...Is it true that a 4.2L crank and rods out of a 258 with serpentine belt will be a direct bolt in, and require no other changes in the rebuild? If so, and the nv3550 will handle a stroker, and reliability and gas mileage will not be greatly affected, I think I might go for it. hm???
 
An NV3550 should handle the average stroker just fine. Grandma type drivers can usually get AX15s to live behind them.
 

$1400 3" Body Lift

I did the swap in a 95 from the 2.5 to the 4.0 and regret that I did not do it soonier. We had no problems other than trying to figure out which brackets from the 2.5 worked with the 4.0 and which ones I had to replace. If anyone is interested I have another 2000 4.0 complete with the computer, transmission and transfer case that I was going to put in another jeep but just haven't had the time. The milage on these are about 6000 miles.
 
Well I just got back from pick n pull. I was there from 9am to about 2pm, and for $316 came home with a complete long block engine and ax15 transmission combo w/clutch and all that stuff, wiring harness, ignition stuff, computer, shifter, intake stuff, carbon canister, and some other miscellaneous junk that I pulled from the now gutted cherokee. I'll rebuild the 4.0L into a stroker (saw an untouched 4.2L with serpentine belt there that I'll have to go back for to get the crank and rods), and am deciding whether or not to rebuild the ax15 or just keep looking for an nv3550 and sell the ax15. Also, the engine has a sanden a/c compressor...not sure if I should use is for oba or try to adapt my york to it and sell the sanden. Oh, and does anyone know how to hook up the clutch linkage? the cherokee had a hydrolic clutch linkage. Well I've never been this greasy or sweaty (it's been in the 90's and the humidity is through the roof), but i think that overall I had a successful junk yard run.
 

RE: Re: RE: Re: toyota 4 banger

djak12, how much for the engine, transmission, etc?
 
the sanden will work fine - just oil it (simple as oiling a filter w/compressor oil) - you have enuff work to do - dont look for more adapting the york to do the same job! (just my $.02)
 
One slight problem...I think the transmission may be a peugeot ba 10/5. It has a two-piece case, though the first gear has a ratio that is closer to that of an ax-15. Well, back to searching for a transmission. So how hard is rebuilding a manual transmission? Idealy I would like an nv3550, but they seem hard to come by. I bet I could find an ax15 and rebuild it, or buy a rebuilt one for around $750 w/o a core.
 

RE: Ok, I

Peugeot transmission?.....What year is it?

You're gonna want to get a 91+ HO cylinder head for that stroker.
 
Re: RE: Vibes at speed

It's an '89. I was going to get a '94 but thought i saw an ax15 so I went for the older engine and transmission. I'll be making another trip to pick n pull soon for the 258 crank+rods and HO cylinder head...I'm gonna have alot of parts left over to sell on ebay and craigslist. Also, does anyone know what bell housings I can use with the ax-15 and nv3550 transmissions?
 

I gotta get me a 258 and put the guts inside my 4.0 sitting out back. I could have had a 258 for $40 last year and I let it go.
 
Considering the value of complete running 4.0L engines, I just couldn't resist pick n pull's engine sale...Today I went and got a 1994 4.0L engine with significantly fewer miles on it for $130 w/core+tax. I'll rebuild that one and use the other for parts and sell it when I'm done. About the transmission, I really don't know that much about the AX15's and BA10, only that the one I have has a two piece case...maybe it's not the original transmission? Anyway, I think I'll keep looking for an NV3550. Oh, and you won't believe this. Last night my buddy saw a listing on craigslist for a free 1977 DJ-5 that was going to the wrecker on Sunday. Since we both are going out of town today, we decided at 9pm last night to go and get it. Turns out there were two, one with a complete engine and drivetrain, the other with everything but the transmission. Both have inline 6 engine with roughly 30,000 miles on them. Well I think I found my 258 crank and rods for the stroker, and will be able to sell the jeeps or part them out to help finance my engine and transmission swap.
 

http://www.jeeptech.com/wiki/index.php/Transmission/Factory

Just click on the one you think you have, and a pic and description will come up. Both of the possibilities are there, so ID should be easy.


You can do some nice stuff with that 94 cylinder head. If you choose to not go the stroker route, do some research on doing a HO head conversion on the 258 before you just drop the 4.0 in. A worked HO 4.2 can be strong.

While this build goes in a slightly different direction than most Jeepers go, it's got alot of good info in it and gives a good idea of what can be done with a mildish stroker build.

http://www.jeep4.0performance.4mg.com/
just follow the links to specific sections at the top of the page
 
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