OM617 Mercedes Diesel

Anyone running a successful OM617 conversion? I see a coulple posts from guys thinking about it but would like info from someone who has done it.
Is it worth it? How do you mount it? C4 adapter? How does it feel? Enough power?
I'm burning veggie oil in my '83Benz now and figure if I could do that in my Bronco, I could actually afford to drive it!

I saw one that a guy swapped engine and transmission but he only had the back axle hooked up (I kind of think that is cheating). I have been thinking about the OM617 as well. I can pick up a runner right now for $500. I think if you are going to go with the OM617 you may be better off going with a Chevy transmission and adapting it to a Ford drop transfer case. There are adapters for Chevy and Mopar transmission but I have yet to see one for Ford. My problem is I am really familiar with the OM617 and the other Mercedes diesel, I am just not a transmission guy, so the the transmission behind them is a mystery to me, I don't know what the tail housing looks like so I don't know if it can be adapted, if it could it would probably be easier to swap the engine and transmission and adapt it to the stock transfer case. I do know their M series has a AWD transfer case behind it called the 4Matic so I would assume that the tail housing can be swapped for a 4WD. I know that the G series has a real transfer case behind it, but apparently the G transmission is a little different, either closer to the Unimog or the same transmission as the Unimog but from my research they are rarer than hens teeth and cost prohibitive. The thing about the OM617 is it is externally balanced so if you do adapt it to a Ford tranny you will have to adapt a balance a Ford flywheel to the OM617. To me this is the biggest pain about doing the adapters myself and why I would lean toward a Chevy transmission or even better adapt the Mercedes transmission to a transfer case. Take a look here on the balancing issue: http://www.mbca.org/forum/om617-torque-converterflywheel

There is also some fab work that needs to be done to the oil pan to clear the front axel but that is not that big of an issue.

Thanks for the feedback, I have a freshly rebuilt C4 in the truck now that I would like to use, Im hoping there is someone out there that has already made this work. This is a project that I can easily avoid if it is too costly or unpractical, I'm not looking to be a pioneer...
The link about the balancing issue seems to focus on a manual trans.,would auto. be much different?

Will the shift points on a C4 wotk with a diesel?I havent read much on how guys are doing that, but I figured with all of the powerstrokes going in, they used the original tranny/t-case setup. Just a thought. Good luck with your build! I'll look forward to seeing pictures!

biobiegun said:

Thanks for the feedback, I have a freshly rebuilt C4 in the truck now that I would like to use, Im hoping there is someone out there that has already made this work. This is a project that I can easily avoid if it is too costly or unpractical, I'm not looking to be a pioneer...
The link about the balancing issue seems to focus on a manual trans.,would auto. be much different?

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I am afraid that you are going to be a pioneer if you try to use the ford trans. They have been adapted to Chevy, Mopar, Toyota and NV transmissions. The some of the Mopar and NV trans have stock tail-housings that will bolt up to the 20 I believe.

As for the Auto, the OM617 is kind of different in the fact that it is externally balanced so while it was bolted to an auto trans it has a flywheel. The trick is to add the same amount of weight to balance the engine and the flexplate for the auto you are going to adapt to. If you want a simple swap you will have to swap trannies too. If not, you will have to build the adapter and equalize the weight of what you are pulling in to balance the engine (a machine shop can do this for you). For me personally the adapter is not that big of a deal, you just trace the transmission and the engine onto some aluminum and cut out the outside lines. Drill the holes from a template you create and bolt it all together.

These guys sell a bolt up adapter for GM and Toyota:

http://www.4x4labs.com/products/diesel-conversions/ (edit: after looking at the site it looks like they only do Manual trannies.)

These guys sell adapters for Jeep transmissions, I think they only do Manuals:

http://mercedesdiesel4x4.com/Products.aspx


I have never used either of their products, so I cannot comment on the ease of use. I would say that the OM617 and Mercedes diesels in general present some unique problems in the fact that they are externally balanced. And the fact that you have to modify the oil pan to adapt it for use in a solid front axle vehicle. Neither are hard and have been done for other applications so the info is readily available. If you can run a plasma cutter you can cut an adapter, balancing can be done by a machine shop, and if you can weld the oil pan is a simple job.

fastcarkenny said:

Will the shift points on a C4 wotk with a diesel?I havent read much on how guys are doing that, but I figured with all of the powerstrokes going in, they used the original tranny/t-case setup. Just a thought. Good luck with your build! I'll look forward to seeing pictures!

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Generally you can get away with the same converter you just loose some efficiency, converters behind diesels usually have a lower stall speed so they lock up sooner. Where the gas one will lock up later. You can usually go from gas to diesel and just loose some efficiency that you could be getting and it may feel a little looser. It is usually more noticeable when you go the other way, put a Gas engine on a diesel tranny. and it has the lower stall speed in which it wants to lock up before the Gas engine has made it to the right speed. That being said a lot of people opt to replace the converter with one that has the correct stall speed because even if it only adds 1 more MPG it will pay for itself in short order. Take this info with a grain of salt though, I have done some diesel swaps but I am by no means a tranny person. I know diesel and how to get them hooked up to a transmission but my transmission knowledge is not that great.