om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

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ChiefLilBigEar
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om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by ChiefLilBigEar »

Hello,

I have planned to swap an om617 into my 79 Cherokee. I have sourced a T-18 out of an old Bronco that is already mated to an NP208. In the Jeep I have a Dana 20. I am looking at getting a flywheel out of a 240D and a conversion kit from Mercedes diesel 4x4. just starting the process of getting parts together. Brought home an 85 300D with Turbo and a T18/np208 combo last week. Still in the gathering stage.

I am wondering if I should keep the NP208 that is already mated to the trans or the Dana 20 that is already in Jeep? Opinions on the plan as a whole?
I am looking at running at largest 33s will be Daily Driving and some offroad.

- Thanks for your opinions.
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Stuka
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Re: om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by Stuka »

Well, neither of them will work out of the box.

You have a passenger side drop front axle. The NP208's are both going to be drivers drop. And, if either of them is a Jeep T18/NP208, its going to have that super long adapter which means it will most likely hit your fuel tank.

Is your current D20 bolted to a T18 also?
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

Billybob535
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Re: om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by Billybob535 »

Steer clear of the mercedesdiesel4x4 kit. The ones they have sold over the last few years have had a lot of issues and caused a lot of people damage. If you look in the 617 groups on facebook you will see details of the problems.

Take a look at the kit from doomsday diesel. His kit is far superior to the mbd4x4 kit.
https://www.doomsdaydiesel.net/product- ... dapter-kit

You can remove the ford bellhousing from the T18 you have and bolt a Jeep T176 bellhousing to it (same butterfly bolt pattern). That will give you the AMC bellhousing to block bolt pattern to work with the om617/Jeep adapter kit. You will need to check the input shaft spline to make sure there is a compatible clutch kit (the doomsday kit uses stock clutch kits - and offers a Jeep T18 flywheel option). I don't think there is an easy solution to mating a passenger side drop transfer case to the Ford T18 without spending hundreds on an adapter. It would be cheaper/easier to just swap your 79 passenger side front Dana 44 for an 80+ drivers side drop Dana 44. Its a bolt in swap and they are cheap and plentiful.

rocklaurence
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Re: om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by rocklaurence »

Id opt for the AX15 vs the T18. Strong enough and has overdrive that is needed for hi way speeds

230ohc
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Re: om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by 230ohc »

I've done this swap with jeep long t18, dana20.

I plan to do ax15, dana 300 for better drivability, but it is thoroughly enjoyable as is.

I had moderate amount of modifications because 1964.

But completely smog exempt.

Despite some limitations of current build configuration it is almost too enjoyable to change.

Good luck with your build I hope it brings you happiness.
1964 willys wagoneer
Om617 turbo diesel
Ax15
Dana 300
3.73 dana 27 front
3.73 dana 44 rear

230ohc
Posts: 430
Joined: Thu Jun 16, 2016 2:27 am
Location: Northern California

Re: om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by 230ohc »

Billybob535 wrote: Mon Nov 09, 2020 2:49 pm Steer clear of the mercedesdiesel4x4 kit. The ones they have sold over the last few years have had a lot of issues and caused a lot of people damage. If you look in the 617 groups on facebook you will see details of the problems.

Take a look at the kit from doomsday diesel. His kit is far superior to the mbd4x4 kit.
https://www.doomsdaydiesel.net/product- ... dapter-kit

You can remove the ford bellhousing from the T18 you have and bolt a Jeep T176 bellhousing to it (same butterfly bolt pattern). That will give you the AMC bellhousing to block bolt pattern to work with the om617/Jeep adapter kit. You will need to check the input shaft spline to make sure there is a compatible clutch kit (the doomsday kit uses stock clutch kits - and offers a Jeep T18 flywheel option). I don't think there is an easy solution to mating a passenger side drop transfer case to the Ford T18 without spending hundreds on an adapter. It would be cheaper/easier to just swap your 79 passenger side front Dana 44 for an 80+ drivers side drop Dana 44. Its a bolt in swap and they are cheap and plentiful.
I personally have used the kit, as well as motor mount, and oil cooler adapters from them.
Zero problems. But I do have some mechanical and fabrication experience. Never the less I am happy with their products for the om617. I have "heard" of issues with the 606 607 type motor adapters but do not personally know of any first hand issues.
1964 willys wagoneer
Om617 turbo diesel
Ax15
Dana 300
3.73 dana 27 front
3.73 dana 44 rear

230ohc
Posts: 430
Joined: Thu Jun 16, 2016 2:27 am
Location: Northern California

Re: om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by 230ohc »

As of Dec. 31 2022 Mercedes diesel 4x4 is out of business.
1964 willys wagoneer
Om617 turbo diesel
Ax15
Dana 300
3.73 dana 27 front
3.73 dana 44 rear

rocklaurence
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Re: om617 Ford T-18 1979 4 dr Cherokee - Transfer case selection

Post by rocklaurence »

rocklaurence wrote: Tue Nov 10, 2020 9:34 am Id opt for the AX15 vs the T18. Strong enough and has overdrive that is needed for hi way speeds
Agreed, this is a better option. Also, plan on re-gearing to help that little diesel.
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