This is a old thread but worth bringing up to help others.

There are a few options for bolting the OM617 to the NSG370 or AX15 transmissions. www.mercedesdiesel4x4.com has a good reputation and is affordable for clean transmission to OM617 adapters.

The NSG370 is a good optio for the OM617 tanks to its aggressive gearing. The 5 cylinder MB is not a powerhouse and likes to rev so the 4.46 first gear really helps get things moving. Also the 0.84 overdrive is modest and with the correct tire/gear combo can help keep the OM617 where it's happy at from 2600~3000 rpms.

Gearing is critical with any OM617 swap and I would still recommend a 3.55~3.73 gear ratio even with a 28 inch tire.

For bigger tires like 31s I would strongly consider 4.56s if you live in the mountains and never drive over 75mph. If you live in flat areas or drive 75+ mph often then maybe 4.10s

For 33+ inch tires look at 5.29s for best performance or if you live in the mountains. 4.88s may work ok with 33s if it's flat and your in a smaller rig.

35s just go 5.29s or bigger. End of story.

 

There's a few different NSG370 bellhousing patterns too. Here's the version that fits a 3.7L V6 in a Liberty. I believe it's a match for smallblock dodge...