Manson_magot Posted April 8, 2016 Share Posted April 8, 2016 Hey I have a 87 mj 2.5 4 speed I also have a rotted out 95 xj 4.0 5speed. How can I Frankenstein these things to make a monster. At sensible cost. Would like to make 4wd and upgrade to the 5speed trans . Any help is appreciated. Link to comment Share on other sites More sharing options...
Eagle Posted April 8, 2016 Share Posted April 8, 2016 The problem is that the 4.0L transmission has a larger bellhousing than the 2.5L transmission, so you can't attach the '95 transmission to your engine. BUT ... When Chrysler was using the AMC 2.5L engine in Dakota pickups, they used it with the same AX-15 transmission as your '95 XJ. So what you would need to do the swap you have in mind is a bellhousing from a 2.5L Dakota. Oh, and you'll almost certainly have to have the length of your driveshaft altered. Link to comment Share on other sites More sharing options...
gogmorgo Posted April 8, 2016 Share Posted April 8, 2016 And the gear ratios won't match between the XJ front and MJ rear, so you'll either have to regear one of them or weld new spring perches onto the XJ rear axle. Link to comment Share on other sites More sharing options...
Manson_magot Posted April 8, 2016 Author Share Posted April 8, 2016 Ur saying the guts of the xj would fit it the dakota bellhousing and what if I sped both xj axles under mj would I still have gear ratio problems Link to comment Share on other sites More sharing options...
88whitemanche Posted April 9, 2016 Share Posted April 9, 2016 So what are you trying to do exactly? Swap the complete 95 engine trans transfer case into the mj? The 4.0 axles have 3.07 gears as the 2.5 has 4.10s.... Link to comment Share on other sites More sharing options...
gogmorgo Posted April 9, 2016 Share Posted April 9, 2016 You for sure can "sped" the XJ axles under the MJ... If "sped" means what I think it means. But bear in mind that 1) the XJ rear axle will NOT bolt into the MJ, you'll need to weld on new spring perches in differed locations; and 2) if you think the 2.5 MJ is slow now with the 4.10 gearing it has, just wait till you try the 3.07's from the XJ... You won't have the problem of mismatched gear ratios, but you might want to try driving only using 3rd and 4th, cause that's what 1st and 2nd will seem like with the XJ's 3.07's. Link to comment Share on other sites More sharing options...
Manson_magot Posted April 10, 2016 Author Share Posted April 10, 2016 Yes I ment swaped. My goal is to make a beast. Trying to figure out if it's worth my time to take anything of the xj. 87 2.5 mj is gutless but with 70k original miles and a slight tick. I loved driving the 95 xj. Wasn't a beamer but lot faster than the mj. 4wd would be awesome but not an absolutely need. Link to comment Share on other sites More sharing options...
Manson_magot Posted April 10, 2016 Author Share Posted April 10, 2016 Original plan was swap motor trans axles transfer case from 95 xj and put into mj. But all the research leads to a 6 month pain in the @$$. Can I make it 4wd with a dakota transmission. And maybe just build up my 2.5 hear they are just as bulletproof as the 4.0s Link to comment Share on other sites More sharing options...
gogmorgo Posted April 10, 2016 Share Posted April 10, 2016 There are a few guys here who have built 2.5's. If you do want to use the XJ stuff as-is, you're best off using all of it. Engine, trans, axles, wiring harnesses, instruments, radiator... Everything. Pretty much everything supporting the 4.0 will have to come along with. If you are planning on going beast and actually doing something other than street driving you'll want a beefier rear axle than the 27-spline 8.25 in the XJ, but it'll likely hold up well enough behind the 2.5l with ~33" tires. If you do want to continue with the 2.5, the Dakota 2.5L bellhousing will be all you need, the XJ trans will work. Just leave the MJ's rear axle as is and regear the XJ front to match. But if you're going to be putting larger tires on it, you'll for sure be wanting more gear than 4.10's. All of this info has been converted many times. Try going through the "your project MJ's" and "DIY" forums on here to see what other people are doing and get ideas. Link to comment Share on other sites More sharing options...
Manson_magot Posted April 10, 2016 Author Share Posted April 10, 2016 Thanks for all the ideas I'll have to do more research before I make up my mind . Would seem like such a waste to not use either motor Link to comment Share on other sites More sharing options...
Manson_magot Posted April 10, 2016 Author Share Posted April 10, 2016 As far as a lift goes will s 10 springs and thunderbird coils still work for mj? I know xj bolt right up Link to comment Share on other sites More sharing options...
gogmorgo Posted April 10, 2016 Share Posted April 10, 2016 Well, it's one or the other, not neither. The cheapest way would be to swap everything over from the XJ. Only things you'd need to spend on in that case would be fuel gauge sending unit, rear axle perches, and rear driveshaft length. But if you're wanting to go beast mode, which I'm assuming means big tires, huge lift, and high horsepower, you'll be needing to upgrade most of the drivetrain anyway, so swapping stuff in right now seems like a bad idea if you're just going to tear it all out again. Link to comment Share on other sites More sharing options...
88whitemanche Posted April 10, 2016 Share Posted April 10, 2016 To just do a 4wd swap that ax15/np231 in your xj can be swapped into 4cyl... I've done it...but you would have to regear your front axle to match your Comanche rear axle gear ratio.... By that time you have to make a decision wether you want taller gears to get some power back into that 4cyl and a better rear axle to swap in.... Link to comment Share on other sites More sharing options...
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