to swap or not to swap.....

ok, so basically I've had this idea that I really want to do... it involves swapping a mercedes diesel engine into my xj. The thing is, I can't find anyone who will make a custom adapter plate to mate the engine to my AX-15 transmission... so, my question is, does anyone know of any companies (preferrably in california) who make custom adapter plates? is this completely impossible? am I an idiot? I'd like to use the jeep trans, but it I can adapt the mercedes trans to the transfer case, I might do that too... any ideas are greatly appreciated! :yelclap::gee:

Have you tried calling Advanced Adapters? They might be able to custom make you one. They are in Paso Robles...

I e-mailed them, and the guy said that they don't do custom adapters... "they have enough work already with their product line" or something like that

huh that sucks... i know there are companies that do it, possibly find a local machine shop to do it? Lemme look in some magazines i have, i thought i saw a couple companies in there.

yeah, it does suck... cause they're fairly close... only a couple hours. I have been told machine shop, but if there is anyone who makes adapters already, that would be best... and probably cheapest.

I too have been VERY interested in doing this. I think that there are others. If you find a shop who will make adapter plates for you, we might be able to drum up a group purchase to make it more worth their while.

I believe that there are other concerns with this swap, however. I saw an MJ with a Merc. 5 cylinder in it, but his rig was 2wd and he just used the Mercedes trans. His major problem was clearance between the front differential housing and the oil pan. His MJ was originally 4wd, so he just swapped in the straight 2wd front axle without a pumpkin and his problem was solved. It's not just a matter of building a custom oil pan either though because the oil pump sits right where the clearance problem is. I saw one guy try to adapt an electric remote oil pump. He then built a custom oil pan similar to the XJ in shape. His engine seized after about 5000 miles, evidently he wasn't flowing enough oil. I saw another guy who pulled off this swap while keeping his 4wd. His solution was 8+" of lift and LONG bump stops to keep the differential off the oil pan. He built his own adapter plate and flywheel to bolt to the AX-15. He also wound up plating the entire front part of the frame with 1/4" steel after the first set of mounts shredded the XJ sheet metal. The last person I saw attempt this decided to mount the engine higher in the bay. This led to severe cutting of the trans tunnel, followed by a messy rebuild of the area. Then the paint on his hood fried because the motor was too close to it. Overall, that one was a hack job. I don't mean to discourage you, but I've done a lot of reading (and dreaming) about doing this conversion. It's just not as easy as coming up with an adapter plate (although that would be a major step in the right direction). If you can figure out a way to make it work, I will be the first to congratulate you, and then promptly copy you. Btw...for the record, the three examples I cited did make it work...sorta. It can be done! I park my 300 Wagon next to my XJ every day with the hope that one day the two might become one. lol Seriously though, if I can be of any help I'd love to work together on this. If you need pictures of either vehicle or have specific questions about the components, I'll do my best to lend a hand.

Unless you're set on the Mercedes motor, I know that guys have pretty good success with the Cummins 4bt swap. Not nearly as pimp as popping the hood and seeing the Mercedes star though! Good luck!

First of all, thanks for that info... and now on to everything else I'mna say...

I thought that the mercedes engine was about the same height as the I6...? I don't know why the oil pan would hang lower... It seems like the lower profile of the mercedes hood area (as opposed to anything the 4bt would come in) would fit the XJ nicely. I was looking very hard at the 4BT for a while, but found that it is a very tall engine. you'd need like 10 inches of lift to fit it. it's a really big 4cyl. you can also soup it up REEALLLY easily to give it well over 200HP I've heard that there is a screw you can turn to get like 400HP! sounds nutzz, I don't know if I believe it... They're also pretty hard to find around here. The 6bt on the other hand, is pretty common, BUT they're HUGE!!! I don't think there's any way you could fit one into an XJ. Anyways, I've done a lot of looking for engines, and I think the mercedes is just an easy route to go. it's very common, and they're pretty cheap. it seemd like it would fit nicely, etc... I've also seen that the isuzu diesels would probably be a good fit. I wouldn't mind one of those, but they're pretty hard to find. My main hurdle right now is finding someone who'll do custom adapter plates. if you have any other ideas of what engine could be used, by all means throw it out there!

taylor. i think you need to put some pressure ($$$) on advance Adapters. that way i can pick it up for you and bring it when i come back to salinas. and after. we can hit up hollister for a test run....lol...

uh... chris... it's gonna take longer than two weeks..... with only a few hours a day at the shop, and time to get parts it takes a while..... I'm not convinced that advance would do it unless I offered them big bucks..... which I don't have.

You could make you own adapter. If you have the diesel motor make template of the bolt pattern then make a template for AX15 bell. You can take piece flat stock aluminum or steel and have a machine shop drill it out or do it yourself if you are handy with drill press. Then you will have to figure out a clutch Chevy used 10 tooth disc just like jeep so that gives you a ton of sizes to choose from. Other thing you need check make sure flywheel on the diesel will fit. And on your adapter plate make sure you locate the starter hole. And hole for the crank. Plus make sure the input shaft will not bottom out in the engine. Pilot bearing can be machine by machine shop. If there is a will there is a way.

call Novak they are based in UT

Here's a link to an MJ with a 4bt. I'm still trying to locate the Mercedes builds I was talking about.

http://www.4btswaps.com/forum/showthread.php?t=585

hi everyone, I found this thread at the right time ...

just doing this swap in my XJ... after hours and hours reading and thinking, I decided to go for OM 603.960 from W124 mercedes 1991 (preferences 147 hp 272 Nm). Was really difficult to find it in Evrope, especialy in Czech. At the end, I bought a car, took the engine off and sold the rest... Expensive but... there we are
I let my mate to check the engine and is in perfect condition, 190.000 miles with no problem at all... inside it looks nice, just let do a engine head renew and put new gasket. So engine is almost ready to go...
I have got the AX-15 transmission ready as well, my cherokee was a 2,1 renault diesel before with weak AX5 transmission in.

So as I see I have the same problem as you guys, cause I can not buy adapter plate here and I not very sure about a clutch neither... I do not know if to use everything from mercedes (flywheel and the rest) and put the jeep clutch disk in or use everything jeep... sould be probably better to use flywheel from mercedes (because the starter)... :read:

I think that the possinbility to use a mercedes trans is rot, because we would have to work it up how to put it together with NP transfer-case, it means another crossbar unerneath and problems with driving shafts and balance...

If you would like me to mesure anything, let me know, I have everything what we need to put it together - engine, AX15 trans and original mercedes trans(automatic)....

so how we will make it works?

If you still havent made up your mind
look for the toyota 1KDFTV its a 3.0l 4 banger turbo IC with 350 NM & 160 bhp

& the best part is that it will bolt to the AW4 by swap the bell housing with A340 tranny

probably too late, already have the engine rebuilt...

so could you give me some advice how to put the engine together with AX15? I mean how you fixed the clutch please?

thanx

Just for kicks, I pulled the motor and trans out of my Mercedes the other day. I've now got the complete drivetrain sitting on the floor of my garage along with a spare AX-15. I'm going to be taking some detailed measurements of both my Jeep and the Merc. drivetrain before I put it back in my wagon, and I will post my findings in a few days. If anyone would like to come up with a "shopping list" of desired measurements, I will be sure to take them. I'm very interested in helping someone pull this conversion off, I'm just not convinced that I have the ability (or the shop, or the time) to be the pioneer.

Like I said in a previous post though, I've got both an 85 300TD and a 97 4.0L,AX-15,NP231 XJ (and a spare AX-15 kicking around the garage) and I'm more than happy to answer any questions pertaining to either vehicle and/or take pictures of anything.

Somebody NEEDS to pull this off for the rest of us to copy! :cheers:

Somebody NEEDS to pull this off for the rest of us to copy!

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NO KIDDING!!!

a new thought is to mate the transfer cast to the exisating mercedes tranny. how hard would it be to do this? is there a flange that we could attach something to to mate it with the t-case input shaft? Maybe fab something for the t-case shaft that would bolt to the tranny output? then fab some case for it? that's my $0.02 more...

as for measurements... try to get an idea of how difficult it would be to adapt the AX-15 to the Merc engine... input shaft size/spline count, bellhousing adapter, flywheel, clutch plate, etc...

tayman said:

as for measurements... try to get an idea of how difficult it would be to adapt the AX-15 to the Merc engine... input shaft size/spline count, bellhousing adapter, flywheel, clutch plate, etc...

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Will do. Adapting a transfer case to the existing Mercedes tranny is the conclusion that I've also been coming around too. I would prefer to make this fit the AX-15, but I really don't have the ability or resources to be machining custom adapters or pilot bushings. Dropping the motor and trans in as one complete unit should be pretty easy (and extremely tempting now that it's sitting out on my garage floor). All things considered, the Mercedes Auto tranny isn't all that bad of a deal either. Unlike most autos, it can be bumpstarted and it will hold in gear for good compression braking/descending. The 240D's had a manual 4 speed, so you can sometimes get ahold of them too, but that auto is by far the most prevalent. As far as divorced transfer cases go, I know that a divorced NP205 would be a fairly good option. There is also a company that makes an adapter to divorce a toyota transfer case. This case would be a lot lighter and smaller. There is also a rare version of the NP242 that was divorced. The NP242 and NP231 share many of the same internal parts, so it might be possible to build a divorced NP231. I would then just pay a driveline shop to make/alter driveshafts for me and I'd be home free. The output yoke on the Merc. tranny is connected to a rubber disc, so there is a provision for a little bit of "play" if things don't get lined up quite right. I think that this is a good option for a "Stage 1" build. I really just want to get rolling on diesel (WVO in my case) and then continue to improve things as time, resources, and new developments present themselves.

Heading down this road though, I really need to find out first hand how big of a problem this differential-to-oilpan clearance is. I used a leaky front crankshaft seal as an excuse to pull the Merc. drivetrain this past weekend so that I can explore this a little. I'll keep posting back as I find out more.

Back to adapting the motor to other transmissions....there is guy who sells an adapter to bolt the Mercedes diesel to a Ford NP235 4spd. tranny. He builds Land Rovers, but I don't see any reason why we couldn't use the same transmission. Advance Adapters makes plates to bolt just about anything to that NP235. His website is: http://www.seriestrek.com/

Talk to the MOG guys. They have the Mercedes diesels bolted to all sorts of trans configs. AX-15 may not be strong enough.

Did anyone reply to the Czech guy's question?