Questions on Cummins swap

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v8vendetta
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Questions on Cummins swap

Postby v8vendetta » Thu Jul 20, 2017 8:00 am

I am considering doing a Cummins swap on a Wagoneer. However, it seems to me like the best course would be to just set the Wagoneer body on the Cummins frame and trim to size. Is anyone aware of any builds that have done this? I would love to get more information about it.
1976 Jeep J-20
401 V8 w/ CRT HEI conversion
TH-400
--------------------------------------
1989 Grand Wagoneer
360 V8
Blown 727

SJTD
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Re: Questions on Cummins swap

Postby SJTD » Thu Jul 20, 2017 8:34 am

If you're willing to go to the other site User jaber has a thread on such a swap. Might be a truck though.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

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Stuka
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Re: Questions on Cummins swap

Postby Stuka » Thu Jul 20, 2017 10:22 am

There is more than one cummins swap on here. However, you should know it requires some big cutting into the firewall for the engine to fit if going with a 6BT. A 4BT fits significantly better. 6BT also requires a D60 front axle to properly handle the 1200lb engine.
1981 J10 AMC 258 with HEI and Weber 32/36 DGEV Carb, T176, NP208, D44/M23 with 4.56 gears and Detroit Locker, 6" lift, 33x12.50 Cooper STT's, BJ's Offroad Rear Dozer Bumper.
2017 JKU Rubicon Lifted
Pevious Jeeps: 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

SJTD
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Re: Questions on Cummins swap

Postby SJTD » Thu Jul 20, 2017 10:39 am

He was asking about using the Dodge frame but now that you mention it I do remember a guy on here do that.

Can't remember his name though.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

SJTD
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Re: Questions on Cummins swap

Postby SJTD » Thu Jul 20, 2017 10:59 am

Found the one I was thinking of but was a gas motor. Doesn't have the cab intrusion Stuka mentioned.

viewtopic.php?t=8050
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

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Stuka
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Re: Questions on Cummins swap

Postby Stuka » Thu Jul 20, 2017 12:30 pm

SJTD wrote:Found the one I was thinking of but was a gas motor. Doesn't have the cab intrusion Stuka mentioned.

http://www.fsjnetwork.com/forum/viewtopic.php?t=8050


Ahh, thats because that conversion was a 1500 gasser.

Every 6BT swap I have seen on an FSJ requires firewall mods with one exception. And that was a frame swap onto Ram chassis and the instead extended the nose out, which looked terrible IMO.
1981 J10 AMC 258 with HEI and Weber 32/36 DGEV Carb, T176, NP208, D44/M23 with 4.56 gears and Detroit Locker, 6" lift, 33x12.50 Cooper STT's, BJ's Offroad Rear Dozer Bumper.
2017 JKU Rubicon Lifted
Pevious Jeeps: 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

v8vendetta
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Re: Questions on Cummins swap

Postby v8vendetta » Thu Jul 20, 2017 1:44 pm

thanks for the link! And I wouldn't need to beef up the axles, as I would use the Dodge ones already on the frame.
1976 Jeep J-20
401 V8 w/ CRT HEI conversion
TH-400
--------------------------------------
1989 Grand Wagoneer
360 V8
Blown 727

cone
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Re: Questions on Cummins swap

Postby cone » Sat Jul 22, 2017 5:07 am

You don't need to cut the firewall or swap out the jeep axles. I have a 12 valve 6BT in my J20 and it fits just fine. The only thing is I had to use an electric fan because there was not enough room for the original fan. I used the motor, 5 speed transmission and transfer case from a 94 dodge with the jeeps frame, that I strengthened by boxing it , and axles. I have been driving it now for 4 years with no problems.

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Stuka
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Re: Questions on Cummins swap

Postby Stuka » Sat Jul 22, 2017 6:33 pm

cone wrote:You don't need to cut the firewall or swap out the jeep axles. I have a 12 valve 6BT in my J20 and it fits just fine. The only thing is I had to use an electric fan because there was not enough room for the original fan. I used the motor, 5 speed transmission and transfer case from a 94 dodge with the jeeps frame, that I strengthened by boxing it , and axles. I have been driving it now for 4 years with no problems.


How did you fit the radiator and intercooler? All the swaps I have seen don't have room for the engine with those in front of it.

And while yours may be fine, you are exceeding the weight rating of your D44.
1981 J10 AMC 258 with HEI and Weber 32/36 DGEV Carb, T176, NP208, D44/M23 with 4.56 gears and Detroit Locker, 6" lift, 33x12.50 Cooper STT's, BJ's Offroad Rear Dozer Bumper.
2017 JKU Rubicon Lifted
Pevious Jeeps: 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

cone
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Re: Questions on Cummins swap

Postby cone » Sun Jul 23, 2017 4:41 am

Stuka wrote:
cone wrote:You don't need to cut the firewall or swap out the jeep axles. I have a 12 valve 6BT in my J20 and it fits just fine. The only thing is I had to use an electric fan because there was not enough room for the original fan. I used the motor, 5 speed transmission and transfer case from a 94 dodge with the jeeps frame, that I strengthened by boxing it , and axles. I have been driving it now for 4 years with no problems.


How did you fit the radiator and intercooler? All the swaps I have seen don't have room for the engine with those in front of it.

And while yours may be fine, you are exceeding the weight rating of your D44.
The only thing you have to do is use an electric fan, I used a flex-a-lite dual fan set up although the engine runs so cool I ran it for the first year without a fan. I used the original jeep radiator with an aftermarket intercooler in front of it and all of it fits behind a rhino grill although the intercooler is smaller than the original dodge intercooler. I think the 6BT fit better in the jeep than the dodge it came out of, you can still get to the last two cylinder in the jeep, in the dodge they are under the firewall. I did have to use an aftermarket in cap heating unit because I had to remove the jeep heating unit in the engine compartment, the turbo is in the way. I have 14000 miles on it now with no problems and as long as your not off road racing or beating the hell out of it the D44 axle is plenty strong enough. ImageImage

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Re: Questions on Cummins swap

Postby SJTD » Sun Jul 23, 2017 8:47 am

Nice! How about some more pics under the hood.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

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Stuka
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Re: Questions on Cummins swap

Postby Stuka » Sun Jul 23, 2017 10:17 am

Very clean install! Thanks for showing it can be done without cutting. I think the others I saw all tried to use the OEM radiator and intercooler.
1981 J10 AMC 258 with HEI and Weber 32/36 DGEV Carb, T176, NP208, D44/M23 with 4.56 gears and Detroit Locker, 6" lift, 33x12.50 Cooper STT's, BJ's Offroad Rear Dozer Bumper.
2017 JKU Rubicon Lifted
Pevious Jeeps: 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

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jaber
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Re: Questions on Cummins swap

Postby jaber » Sun Jul 23, 2017 5:41 pm

IIRC the dodge firewall (back of engine) to radiator face is 40" and my j20 was 38". I have 3" between the pulleys and radiator. I am being as cheap as possible and am using the dodge rad & intercooler. My threads are screwed thanks to PB.Image


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Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/

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Stuka
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Re: Questions on Cummins swap

Postby Stuka » Sun Jul 23, 2017 6:07 pm

Fixed your photo for you Jaber :)
1981 J10 AMC 258 with HEI and Weber 32/36 DGEV Carb, T176, NP208, D44/M23 with 4.56 gears and Detroit Locker, 6" lift, 33x12.50 Cooper STT's, BJ's Offroad Rear Dozer Bumper.
2017 JKU Rubicon Lifted
Pevious Jeeps: 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

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jaber
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Re: Questions on Cummins swap

Postby jaber » Sun Jul 23, 2017 7:03 pm

Thank you sir
Jeff

'46 cj3a
'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
'77 J-10 p/u
'79 Cherokee
'88 Grand Wagoneer
http://s252.photobucket.com/albums/hh14/jeffaber/

v8vendetta
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Re: Questions on Cummins swap

Postby v8vendetta » Mon Jul 24, 2017 8:05 am

Holy crap, that looks amazing. I owned a '95 12 valve Cummins that I repainted myself a couple years back. Had to sell it. I loved that truck, mostly for it's powertrain. That's why I would like to resurrect that passion with this swap.
1976 Jeep J-20
401 V8 w/ CRT HEI conversion
TH-400
--------------------------------------
1989 Grand Wagoneer
360 V8
Blown 727

cone
Posts: 25
Joined: Tue Mar 26, 2013 4:59 am

Re: Questions on Cummins swap

Postby cone » Tue Jul 25, 2017 4:18 am

If you use the dodge drivetrain you can even use the jeep transfer case shift lever on the Nv241hd transfer case. The last picture is me taking the dodge donor truck to the scrapyard. I did pretty well, I paid $1300 for the truck and then got $750 for the scrap but that was a couple of years ago when the price of metal was better.ImageImageImage

v8vendetta
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Re: Questions on Cummins swap

Postby v8vendetta » Tue Jul 25, 2017 7:53 am

man, you should find me a deal like that :P . Those things go for the price of gold over here
1976 Jeep J-20
401 V8 w/ CRT HEI conversion
TH-400
--------------------------------------
1989 Grand Wagoneer
360 V8
Blown 727

Iceman0502
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Joined: Tue Mar 26, 2013 6:32 pm

Re: Questions on Cummins swap

Postby Iceman0502 » Fri Aug 04, 2017 7:07 am

I will confirm that the 6BT fits in a wagoneer with no firewall modifications. Actually there was one that I made near the trans filler tube since it was very close and didnt want any contact.

I purchased a 94 Ram and used the motor, 47RH trans, and NP241 transfer case with a SYE. new drive shafts were made. The frame was boxed using metal from the old ram, heavy duty j20 front springs and j20 axles (mainly for the rear D60 and wider stance) Factory radiator with the upper port and installed smaller intercooler between the rad support and front valance.

The turbo comes close to the heat box and couldnt be used. I will enclose the heater core and make a custom enclosure with a inline water valve to shut the heat down (eventually) dont really need it in North Carolina right now. Im also a windows down person so AC hook up is not an urgent need.


Overall, its working. I have using it to commute to work lately and take some mileage off my other car. No problems with the drive train. Mainly dealing with other kinks on the truck.... like the front door wont let me out from inside :banghead: lol

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Re: Questions on Cummins swap

Postby Adventure_Wagon88 » Fri Aug 04, 2017 12:28 pm

Dammit now I'm leaning towards a 6BT again. I've only ever found 1 solid good deal on a 4BT in my area and have lately been thinking that a 6BT swap would actually be cheaper and better, though slightly less nimble on trail.


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