87 Grand Wagoneer on 94 Cummins 3500 chassis

[MajorPain999]

This build has been a dream of mine since about the time i got my Grand Wagoneer around 4 years ago. Due to an unexpected transmission failure, I decided to go ahead and spend the money to get a suitable donor vehicle. I searched for a few months before I came up with this.

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It's a 1994 Dodge Cummins 3500 dually. 5.9 12V/NV4500/NP241/Dana 60/Dana 80. Body was absolutely shot but the frame was in relatively good shape. Using a few other build threads of similar concepts as guides, me and a good friend began to draw up how we intended to do it. The Wagoneer's wheelbase was 110" from the center of the wheel wells and the Dodge was 137". We cut 20" out on the flattest portion of the frame and welded it back up, measuring from a bunch of different locations to ensure the frame stayed square.

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We then removed the Wagoneer's body from the original frame with a cherry picker and two floor jacks. It was super sketchy, but without a 4 post lift, we did the best we could.

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[Stuka]

Welcome to the forum. This certainly seems to be a popular swap this year

If you like, I can move this to build threads if you intend on posting up the full build process.

[MajorPain999]

Welcome to the forum. This certainly seems to be a popular swap this year

If you like, I can move this to build threads if you intend on posting up the full build process.

That is fine! I will update with more pictures and info later in the day, and also correct the double posted picture that I missed.

[MajorPain999]

This was the finished product after sitting the wagoneer body down on the shortened frame.

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Next we built body mounts to mount the body at all 4 corners. We did this by basically airing the tires up to ride height to get the frame level, and then leveling the body to the ground. Then lowering the body down to about 1/4" off the frame at the closest spot and squared it up side to side. Then we mounted our mounts to the body and tacked them, remeasured and final weld. The body has a slight rake to it so i will probably be removing the blocks from the rear suspension to correct that. Overall, not too bad, no body cutting needed at all.

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With the body mounted in the correct position to center the tires in the wheel wells, there is a 10" gap from the fire wall to the back of the head of the engine. The front clip will not go back on without correcting this and pushing the engine back. So our next step was to move the Jeep from my concrete slab over to my garage where we had more room to move an engine crane. It also helped to have the roof so the Florida summer rain wouldn't slow down progress on it. With the jeep under the carport it was time to start lifting the drive train and making some cuts for clearance.

[MajorPain999]

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You can see in one of the pictures where we clearance the crossmember for the a/c compressor. New engine mounts were built and then we also had to build a trans mount.

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I may go back and change the way the trans crossmember bolts to the frame, I think it needs a little more meat in the frame for the mount.

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This was the end product of pushing the drivetrain back. The engine now has about 1-2" between the back of the head and the firewall. Thats pretty much caught up on where the project is as off today. I am currently test fitting the front clip to see how i am going to make an engine fan, radiator and intercooler work. There will definitely be some cutting being done to the inner fenders and front clip assembly. Then I have to hook the hydraulic clutch up to my manual pedal assembly and then plumb a fuel system. Looking at options for putting the tank where the spare tire would be. I will also be wiring a separate relay box in to run all the added on electronics such as lights and gauges. Nothing from the OEM gauge cluster will work with what it has now so i will be going with Autometer gauges in a sheet metal interlay. I will try my best to update every step of the way!

[Stuka]

Most people end up notching the firewall to move the engine farther back to allow for the Rad/IC/AC. You may end up having to cut into the front valance.

Many here have used Blazer/Bronco tanks behind the rear axle. I do not know the width of the Ram frame offhand, but its a good place to start.

[MajorPain999]

Took some time to do some basic preventative maintenance on the Cummins while i had access to everything. Cleaned up the valve covers and installed new gaskets and then took the front cover off to take a look at the infamous killer dowel pin.

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I made a little tab out of some scrap and found a longer bolt that fit the boss. Used some red loctite and torqued it, i think itll be fine and saved me a bit of cash from buying the kit online.

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Next I got to work on the radiator/intercooler fitment. I ended up notching the front clip about 3-4 inches and pushed the radiator into that hole for clearance to the engine fan. I then made new feet mounts for the radiator to sit on and modified the stock upper mount to use. With the radiator in place I was able to start making a mount for the intercooler. As of right now I still haven't finished the upper intercooler bracket but it is hanging in its intended location.

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I have about 1/4" clearance between the radiator and the fan blades at the top of the radiator. I think I may shave an 1/8-1/4" off the fan blades to open up that space a little more. I also still need to modify the factory dodge fan shroud to fit the jeep. All in all, being able to retain the mechanical fan is going to be great for cooling. I couldn't find an electric fan that generated anywhere near the CFM of the OEM mechanical fan.

I also fitted the fenders to see where the tires were going to sit in the fender. Looks like the axle got moved slightly forward from where it was on the Jeep frame.

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Those are 33's on it currently, they came off the dodge truck when i bought it. Looks like i have plenty of room for 35's. Maybe even 37's.

[MajorPain999]

So a little update on the Waggy! I got the fuel tank modified and in the frame rails. I had to build a sender for the tank which I will be using with a autometer gauge

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Next, I modified the radiator to switch the ports to the opposite sides for the Cummins.

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I also got the wheels and tires installed. 35" Nitto Terra Grapplers with some d hole black wheels.

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[MajorPain999]

I also got the hydroboost and hydraulic clutch set up mounted and filled with fluid. For the hydroboost, I used a Chevy Astro hydroboost unit with the Dodge 3500 master cylinder. It bolted right up to the firewall with the Jeep adapter off the stock jeep vacuum booster. I used AN PTFE hose with steel AN fittings for the hoses. Used some metric to AN conversion fittings on the all the Pressure lines. I also bent some brake lines to hook everything up on the brake stuff. For the hydraulic clutch, things were a little more difficult. The OEM NV4500 slave uses a oem style plastic hose for the hydraulic line which cannot be modified to work with an aftermarket master cylinder. And the Dodge master cylinder uses a strange mounting bracket that makes it very difficult to adapt to the jeep firewall. The solution was to use a fancy adapter fitting that is designed to go into the OEM dodge slave cylinder and convert it to a -4 AN fitting. Then I mounted a WIlwood master cylinder on the firewall to actuate it.

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This picture shows some of the lines and the mounted hydroboost and master cylinders. If anyone wants to see the fittings I used, I can get pictures of those as well.

Finally I started to reinstall the front clip for the last time, and ended up running into a lot of clearance issues that I thought i had solved already.

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I ended up modifying my Intercooler mount to push it farther out and move the radiator farther out away from the engine mechanical fan. I also had to cut the hood release rod because it was directly in the way of my radiator. I am still working on modifying the mounts i had already made for the radiator and also fabbing up something so i can open my hood easily. I will post some pics of that when I get it figured out.

I also scored some 05 Excursion Limited seats with the heaters in them that i will be swapping in. Here's a pic of them just sitting in the cab, I need to sew the split seam back up on the driver. Not bad for 150$ at the yard!

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[MajorPain999]

I wanted to clarify that I did not weld the frame and leave it that way. I also grinded the weld flush, fish-plated the outside with 3/8" plate and boxed the inside where the cut was at. That area of the frame has added strength all the way around it now. Unfortunately the body mount locations lined up with the area where we cut the frame so I also had to add a body mount there as well.

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