Single-mass flywheel vs dual-mass

[JMRobins]

I'm collecting parts to put a M57N2 BMW diesel into a Jeep XJ. I've been told a single-mass flywheel will make the AX15 loud. A dual-mass flywheel helps and is factory equiped behind the M57's. I just fear it wont survive. Will a dual-mass flywheel survive medium to hard rock crawling? I don't sit there and rock bounce, but it'll definitely get abused.

 

[Gots_a_sol]

Not wheeling related, but I replaced the DMF in my VW GTI with a SMF kit and it is annoyingly loud/rattly at idle, especially with the A/C on. Helpful, I know

 

[TRINDU]

I noticed nothing in a VW TDI.

In a 5.9L Cummins, the G56 had more 'roll over' noise, which was easily fixed by good fluid.

DMF suck.

 

[JMRobins]

Not wheeling related, but I replaced the DMF in my VW GTI with a SMF kit and it is annoyingly loud/rattly at idle, especially with the A/C on. Helpful, I know

Thanks for the info. That actually helps a lot. Ultimately, reliability is most important, but I'd like the Jeep to be as quiet as reasonably possible.

 

[JMRobins]

I noticed nothing in a VW TDI.

In a 5.9L Cummins, the G56 had more 'roll over' noise, which was easily fixed by good fluid.

DMF suck.

I'm reading a bunch of negatives with the DMF. They just don't seem to last long, even in the factory BMW's. I think I'll have to just go SMF and deal with any noise it makes. There's a chance I'll need to get a custom flywheel made. Maybe a heavier flywheel would help.

Thanks for the input. I appreciate it.

 

[ThePanzerFuhrer]

I'm collecting parts to put a M57N2 BMW diesel into a Jeep XJ. I've been told a single-mass flywheel will make the AX15 loud. A dual-mass flywheel helps and is factory equiped behind the M57's. I just fear it wont survive. Will a dual-mass flywheel survive medium to hard rock crawling? I don't sit there and rock bounce, but it'll definitely get abused.

Who are you having to do the immobilizer delete and the ecu programming?

You making your own wiring harness? I so want to do this swap to a c10 service truck of mine.

 

[JMRobins]

Who are you having to do the immobilizer delete and the ecu programming?

You making your own wiring harness? I so want to do this swap to a c10 service truck of mine.

There are a bunch of European companies that sell ECU's with different levels of deleted items (emissions) and power levels. Usually between 4-500 dollars. I've seen some US companies too, but I'd have to look again to find them. There's also the DID1 stand alone computer, but it's 1200 bucks and I'm not interested in doing the mapping from scratch.

I'm planning on doing the wiring myself, but there are companies that sell ECU's with simple harnesses that would make it almost plug and play. As far as the XJ goes, I think I'm leaving the Jeep computer in there to keep my dash and cruise control working.

 

[ThePanzerFuhrer]

There are a bunch of European companies that sell ECU's with different levels of deleted items (emissions) and power levels. Usually between 4-500 dollars. I've seen some US companies too, but I'd have to look again to find them. There's also the DID1 stand alone computer, but it's 1200 bucks and I'm not interested in doing the mapping from scratch.

I'm planning on doing the wiring myself, but there are companies that sell ECU's with simple harnesses that would make it almost plug and play. As far as the XJ goes, I think I'm leaving the Jeep computer in there to keep my dash and cruise control working.

Start a build thread on this please. I would really like to see how you do this!!!

 

[fl0w3n]

When I read “quite as possible” and “diesel” I rolled my eyes and then had to look up the motor on YouTube… damn that thing just purs. Hadn’t heard of that swap before.

I second the thread, please share.

Do you anticipate this winding out cheaper than an R2.8 swap? How’s the weight and size compared to xj engine compartment?

 

[JMRobins]

When I read “quite as possible” and “diesel” I rolled my eyes and then had to look up the motor on YouTube… damn that thing just purs. Hadn’t heard of that swap before.

I second the thread, please share.

Do you anticipate this winding out cheaper than an R2.8 swap? How’s the weight and size compared to xj engine compartment?

R2.8? I know this is gonna be controversial, but that motor is a waste of money. 8.5K for a motor, 1,250 for an adapter kit, and 160hp/310 pound feet of torque, and you still need a transmission. People say its max power is just about 185hp and 350 torque. That's a whole lotta money for a 700 pound hunk of outdated technology. I hate to say it, cause I fully wish I could support Cummins, but my money goes where its more practical. The R2.8 is a slightly updated 4BT. Look at the M57 platform. It has plastic parts on it, and that sucks. I hate plastic. But the damn thing will do 400hp and 500 pound feet of torque without doing anything but exhaust and a tune. Wanna pull 6K RPM? Throw in some stiffer valve springs. Stock US engines came with a variable vane turbo. People say its pretty reliable, I have no clue in reality. I do know I can throw a compound turbo on it and pull serious power just off idle all the way up to 5k with all factory internals. I'm not looking for that kind of power though. I want a clean and smooth running engine that will allow me to pull all the Colorado passes at 80mph with out going below 4th gear. My JK struggles with just 35's. When I go over Vail pass, I'm rowing all the way down to 2nd gear and holding 4500-5k rpm. I live in Colorado but do a bunch of wheeling in Arizona and California. I'm hoping for a solid 300hp and 400 pound feet of torque. That's should do good when you consider its roughly the same weight as the 4.0.

I know a XJ on 37's and 1 tons wont ever get good mpg's, but I wanna shoot for something higher than my JK gets. 1000 miles in fuel adds up quick.

Right now the Jeep is bone stock. This will be a slow build, but I think it'll be worth it in the end. I'm still in the collecting parts faze.

To answer your cost question, I think I can do the entire swap, with an AX15 for about 6.5k. The M57N2 is pretty hard to find in the US though. They're out there, but I don't think I'll be finding one in the local junkyard.

 

[ThePanzerFuhrer]

R2.8? I know this is gonna be controversial, but that motor is a waste of money. 8.5K for a motor, 1,250 for an adapter kit, and 160hp/310 pound feet of torque, and you still need a transmission. People say its max power is just about 185hp and 350 torque. That's a whole lotta money for a 700 pound hunk of outdated technology. I hate to say it, cause I fully wish I could support Cummins, but my money goes where its more practical. The R2.8 is a slightly updated 4BT. Look at the M57 platform. It has plastic parts on it, and that sucks. I hate plastic. But the damn thing will do 400hp and 500 pound feet of torque without doing anything but exhaust and a tune. Wanna pull 6K RPM? Throw in some stiffer valve springs. Stock US engines came with a variable vane turbo. People say its pretty reliable, I have no clue in reality. I do know I can throw a compound turbo on it and pull serious power just off idle all the way up to 5k with all factory internals. I'm not looking for that kind of power though. I want a clean and smooth running engine that will allow me to pull all the Colorado passes at 80mph with out going below 4th gear. My JK struggles with just 35's. When I go over Vail pass, I'm rowing all the way down to 2nd gear and holding 4500-5k rpm. I live in Colorado but do a bunch of wheeling in Arizona and California. I'm hoping for a solid 300hp and 400 pound feet of torque. That's should do good when you consider its roughly the same weight as the 4.0.

I know a XJ on 37's and 1 tons wont ever get good mpg's, but I wanna shoot for something higher than my JK gets. 1000 miles in fuel adds up quick.

Right now the Jeep is bone stock. This will be a slow build, but I think it'll be worth it in the end. I'm still in the collecting parts faze.

To answer your cost question, I think I can do the entire swap, with an AX15 for about 6.5k. The M57N2 is pretty hard to find in the US though. They're out there, but I don't think I'll be finding one in the local junkyard.

The m57n2 has compound turbos on it allready if you get it from the 09-11 335d. No variable vane stuff. The krauts really have these turbos dialed in. You cannot tell when it switches from the little to the big turbo.

I have 2 of these engines in a 335d and a 535d that we dd. I love them.

My 335d has the big boy tune 109 hp tune on it and a hp tuners tranny. She really rips. It is starting to run out of fuel so the next mod will be a hpfp upgrade.

 

[JMRobins]

The m57n2 has compound turbos on it allready if you get it from the 09-11 335d. No variable vane stuff. The krauts really have these turbos dialed in. You cannot tell when it switches from the little to the big turbo.

I have 2 of these engines in a 335d and a 535d that we dd. I love them.

My 335d has the big boy tune 109 hp tune on it and a hp tuners tranny. She really rips. It is starting to run out of fuel so the next mod will be a hpfp upgrade.

Thanks for the correction on turbo type. I've been looking at so many diesel engines for the swap, they kinda start to blend together.

I'm glad to hear you like the M57's you have. I've never actually seen one in person and truthfully, this will be my first time really working on any diesel. I still have some saving to do, but hopefully I can find one when the time comes.

 

[fl0w3n]

R2.8? I know this is gonna be controversial, but that motor is a waste of money. 8.5K for a motor, 1,250 for an adapter kit, and 160hp/310 pound feet of torque, and you still need a transmission. People say its max power is just about 185hp and 350 torque. That's a whole lotta money for a 700 pound hunk of outdated technology. I hate to say it, cause I fully wish I could support Cummins, but my money goes where its more practical. The R2.8 is a slightly updated 4BT. Look at the M57 platform. It has plastic parts on it, and that sucks. I hate plastic. But the damn thing will do 400hp and 500 pound feet of torque without doing anything but exhaust and a tune. Wanna pull 6K RPM? Throw in some stiffer valve springs. Stock US engines came with a variable vane turbo. People say its pretty reliable, I have no clue in reality. I do know I can throw a compound turbo on it and pull serious power just off idle all the way up to 5k with all factory internals. I'm not looking for that kind of power though. I want a clean and smooth running engine that will allow me to pull all the Colorado passes at 80mph with out going below 4th gear. My JK struggles with just 35's. When I go over Vail pass, I'm rowing all the way down to 2nd gear and holding 4500-5k rpm. I live in Colorado but do a bunch of wheeling in Arizona and California. I'm hoping for a solid 300hp and 400 pound feet of torque. That's should do good when you consider its roughly the same weight as the 4.0.

I know a XJ on 37's and 1 tons wont ever get good mpg's, but I wanna shoot for something higher than my JK gets. 1000 miles in fuel adds up quick.

Right now the Jeep is bone stock. This will be a slow build, but I think it'll be worth it in the end. I'm still in the collecting parts faze.

To answer your cost question, I think I can do the entire swap, with an AX15 for about 6.5k. The M57N2 is pretty hard to find in the US though. They're out there, but I don't think I'll be finding one in the local junkyard.

That’s a fair analysis I think, but I’m not quite sure I want or need 400hp and 500ft/lb in a manual trans XJ

I had 420 wheel HP and around 800ft/lb in my LB7 duramax with a zf6 manual… and that was fucking nuts. That’s not a fast shifting trans but if you could get it to shift fast enough you’d just roast the tires in 2nd 3rd and into 4th. I can’t imagine in something that weighs half that.

Which leads me to my bench racing counter argument- if I want to rip and hot rod a diesel I’d get another Duramax. And a very important lesson I learned owning that very rare sought after zf6 duramax… rare doesn’t always equate to good. A broken tail housing led to replacing the entire transmission because there are so few tail housings in the whole country that I could only obtain one by buying an entire trans. General rebuild parts were rare or hard to find for it.

I haven’t done a diesel swap so I’m just bench racing here, but I think the advantage of the R2.8 is it’s relatively plug and play, which has value to me living in Commifornia, and I hear it gets you the power you need in a lighter rig. It might not hot rod around but that would be fine with me personally.

What’s your take on a TDI swap?

 

[JMRobins]

That’s a fair analysis I think, but I’m not quite sure I want or need 400hp and 500ft/lb in a manual trans XJ

I had 420 wheel HP and around 800ft/lb in my LB7 duramax with a zf6 manual… and that was fucking nuts. That’s not a fast shifting trans but if you could get it to shift fast enough you’d just roast the tires in 2nd 3rd and into 4th. I can’t imagine in something that weighs half that.

Which leads me to my bench racing counter argument- if I want to rip and hot rod a diesel I’d get another Duramax. And a very important lesson I learned owning that very rare sought after zf6 duramax… rare doesn’t always equate to good. A broken tail housing led to replacing the entire transmission because there are so few tail housings in the whole country that I could only obtain one by buying an entire trans. General rebuild parts were rare or hard to find for it.

I haven’t done a diesel swap so I’m just bench racing here, but I think the advantage of the R2.8 is it’s relatively plug and play, which has value to me living in Commifornia, and I hear it gets you the power you need in a lighter rig. It might not hot rod around but that would be fine with me personally.

What’s your take on a TDI swap?

I don't need that power either, but it's nice to know I can increase power easily if I find I wish I had more. My plan right now is to throw it together in stock form. Drive the stock engine in my stock XJ and see how it compares to the 4.0. I may get it dyno'd as well, just cause I'm a very curious person and I like data points. Once I know how it drives stock, I can start thinking about gearing for the one tons and 37's when I finally get that far. When it's on it's final tire size, I'll get it dyno'd again. If I feel its under-powered when I drive it, I'll tune it. I have no plans to go more power than I need. That'll just use more fuel and decrease engine life.

I looked a bit into TDI swaps, but they're also on the low side for power. I want an engine with some easy power left on tap. If I'm doing a swap, I want to do it once and not regret it. The TDI swaps I've read about are great for a lighter trail rig, but they won't hold 80mph with a headwind. And I like that the tach on the XJ matches up pretty good with the M57. I'm picky I guess, but I like things to look and work like they belong together. I even tracked down a NOS factory diesel info center for my dash. I'll be using the factory glow plug light, water in fuel light, and low coolant light.

Also, please keep in mind, I'm as far away from an expert as you can get. I haven't even owned a diesel vehicle. This is all from research. I also looked at OM606, OM617, OM648, LS swaps, and 2.3 Ecoboost swaps. In the end, fuel economy won. Many of my trips are 500+ miles, all offroad. I have to carry 25 extra gallons for my JK on these trips. I really want to see if I can cut that down. The 37's and one tons are cause I also like to do harder stuff. This XJ is gonna hopefully be good at a lot of different things, but won't perform as good as a specific built vehicle.

 

[fl0w3n]

All good reasons, and I support it! I was just curious to hear your thought process in this as I'm always "bench racing" diesel swaps in my head in the future.

You absolutely need to get a build thread going once you get to that point.

I love diesels, I've only owned big American V8 diesels (3 duramax's & 2 6.7 Powerstrokes) but I love them all. They're fun but the newer ones can be costly to maintain. I don't want to get too deep into it but do you need to maintain all the factory after treatment components on the BMW unit?

And to more directly answer your question, my single mass flywheel in the Duramax ZF6 did make some gear rollover noise, but that truck was loud as shit so it's not like it was the only thing clacking and shaking away.

 

[JMRobins]

All good reasons, and I support it! I was just curious to hear your thought process in this as I'm always "bench racing" diesel swaps in my head in the future.

You absolutely need to get a build thread going once you get to that point.

I love diesels, I've only owned big American V8 diesels (3 duramax's & 2 6.7 Powerstrokes) but I love them all. They're fun but the newer ones can be costly to maintain. I don't want to get too deep into it but do you need to maintain all the factory after treatment components on the BMW unit?

And to more directly answer your question, my single mass flywheel in the Duramax ZF6 did make some gear rollover noise, but that truck was loud as shit so it's not like it was the only thing clacking and shaking away.

I'll absolutely do a build thread when the time comes.

I'm not keeping any of the after-treatment things, but if I had a 1999 or older XJ I might consider it. My understanding is with a '99 and below, I'd be able to re-register the Jeep as a diesel as long as it's a 2000 or later diesel engine with all the emissions stuff on it. I'd have to pass inspection and all that crap as well. Ideally, I'd keep it as legal and legitimate as possible, but my XJ is a 2000, so that's not gonna happen.

I think I'm gonna have to go single-mass and deal with the noise. I can use a factory BMW flywheel, but the clutch disk is pretty small. 9.44" (240mm). I'd like to use the factory XJ 10.5" clutch disks, so a custom flywheel may be the route I go. If I do that, I'll get it built heavy. That may help with the noise and will definitely help on the rocks.

Thanks again for all your input.