Cummins First Gen Build Thread (no really)

[Kiliona]

It's been a hot minute since an update, so here we go! Sometimes fabrication just takes a lot longer then you expect it to... but... my explorer now has a dana 50 under the front end! At least, mostly.

So as a recap I grabbed an 8 lug TTB dana 50 out of an F250 in a junkyard. The first issue to overcome was the fact that these axles came with leaf's not coils, so I needed to mount the coil seats onto the dana 50. I did this by welding the stud from the dana 35 onto the 50. It might have been better to find a way to bolt it, however the dana 50 arms aren't as tall as the 35 so there isn't really enough height to have the full stud sticking in there without it hitting the axle shaft I had to cut the stud down. Welding was the best option, and by my second try I even managed to put the stud on the right side of the axle! . This part was easier then I expected it to be for sure.

Now I could bolt the coil springs on, but I needed to be able to bolt the dana 50 to the chassis. First thing was first - to make it easier, I flipped my chassis upside down so I could get at where it needed to be welded easier (this is partially to blame for how I managed to weld the studs on upside down the first time). One interesting thing to note is that I needed to move the pivot brackets about 3" towards the front of the car to make the dana 50 sit in the right spot, that was a surprise. Here is the before and after on the passenger side mount.

The good thing about this is that it meant I was able to get this bracket out of the way of where the 6BT oil pan will sit without changing the wheelbase of the car, so silver linings haha. I had to cutout part of the front of the engine crossmember to get the pumpking to fit on the drivers side, here it is mocked up to test the clearance and such (it received a bit more plating after this point, and don't worry about the axle shaft depth this was just a mockup).

After some plating and a lot more welding, here's the finished product! A dana 50 under a ford explorer. The 8 lugs on an explorer are beautiful .

Now it needs radius arms. I decided to go with a the linkage type I described in an earlier post rather then simply remaking the stock design. Technically what I'm building is a parallelogram type linkage, one of the simplest linkages you can get. With my design the caster will not change as the suspension cycles which should significantly improve the dynamics of the suspension and help to eliminate a few of the issues people have with TTB. Here is what I'm going for. On the left is essentially the stock setup, on the right is my design. Again see post above for more discussion on this:

I went with heim joints and 36" long links. I was able to get all the materials for this for less then $200 on Mcmaster (could of probably saved even more getting the tubing at a metal yard). Using these longer arms will result in ~1.4" of front to back movement of the axle for every 10" of suspension travel (rather then the stock 2.7"+). The length of the dana 50 arms will result in a joint offset of at most 7 degrees which is well within the ability of heim's to meet. Note all these numbers are IIRC, I did this calculation a few weeks ago and the napkin I wrote them on wasn't the cleanest .

I started out by tig welding up some linkages. I'm using a left hand thread heim on one side and a right hand on the other which will give me a couple inches of adjustability front to back on the car without having to remove the linkages as well as allowing me to do a base caster setting through the linkage - should make getting the TTB alignment done much easier. Additionally ride height will no longer affect caster so that will also make aligning it easier.

I then took some 1/4" angle iron that had been lying in my parents driveway for a decade and made some brackets to mount the links on. The side that mounts on the axle is clearanced for the spring and for the jam nuts, the frame side is about 1/4" taller to help the heims and tubes clear the frame. Left side is the axle side, right side is the frame.

Tig had been getting expensive, and I wasn't kidding about where I found the angle iron so the metal was pretty dirty which isn't very tig friendly, so this was my first real foray into stick welding. Next was to stick weld the axle bracket on.

Next in order to get the tubes to fit at full bump stop I had to clearance the body mounts. Here's the before and after.

After this I attempted to weld the frame side mounts on, but had to give in. Overhead stick welds are hard, and this one was above my ability. Luckily my GF was trained as a pipe welder so rather then having to flip the frame over again I got her to come in and weld it. While she was at it we added a plate on the back.

You might be thinking that the bracket removes a lot of ground clearance, and you'd be right. However it's "only" about 5 1/2" which isn't too much more then the leaf spring mounts anyways. That's what the plate on the back is for is I'm hoping with it I MIGHT have a fighting chance to back over a rock with it if I ever needed to but it might be wishful thinking. the reason the mounts are on the bottom of the frame and not the side is that I would have had to completely remove the body mount I clearanced earlier to position the link bracket any higher. If these brackets get in my way too much I can always cut them off and move them, but for now I wanted to avoid having to reposition the body mount.

Here's the finished and painted product! Note the coil spring is removed in this picture so I could set the axle at full bump stop. It's tight but the links and differential are all clearing at full stop (however I SHOULD move the bump stop over a touch, it isn't exactly in the right spot).

Here it is with springs installed

The front definitely took a lot longer then I wanted it to, and there's still some things that need done on it. For example, steering, brakes, and shocks. I haven't welded on a stud for the shock mount yet since I plan on using the 2" lift springs and shocks that are on my green explorer. I still need to find a place to work on the green one and pull the suspension out of it so I won't know how high exactly to put the shock mount until I get the shocks and springs home to test it with.

Next will likely be the rear end which should be much easier then the front. I'll be using the dana 70 out of the ram (same 8 lug pattern as the front) and I won't be going crazy, no 4 link setup or anything "yet" so it should be much simpler. After that I need to do some boxing on the frame, get the drivetrain mounts fabricated up, clutch and gaskets, driveshafts, body back on, burnouts, then figure out all the small stuff like gauges exhaust and fenders . Still a lot of work to do, but it is coming along!

As always if you prefer a vlog to a blog, then here's installing the pivot brackets and coil spring perches in video format:
Swapping Leaf's to coils? 4x4 Axle FABRICATION! - YouTube

and here's the new "radius arms" in video format:
Fixing Everything That's WRONG With a TTB Front Axle! - YouTube

 

[RangerX]

This is all very cool and impressive, but the coolest and most impressive part to me is that your girlfriend came out to weld the spot you couldn’t do! She’s a keeper!

 

[Kiliona]

Another update.

I needed swap the nv4500 transmissions input shaft from a 1 1/8" shaft to a 1 1/4" shaft in order for it to bolt up to the cummins. Started by removing the top (note can technically do this without pulling the top but I wanted to take a look inside).

Synchronizer teeth looked okay but I didn't dig any deeper. Needed to pull the input shaft retainer to get the input shaft out. Note that here it was much easier to have the top off since I could knock the retainer out from the back.

Next I needed to get the race out. The issue is that it's blind, there's no way to get at it from the back. If you're going to do this just buy a race removal tool. I originally tried welding a small plate to the race to pull it out but it broke. Instead I used a holesaw to get a piece of plate the shape of the race and welded the whole thing in. The good news with this method though is that it was hot enough I could just throw some water on it and hammered it out, no press required.

After this I put the new bearing on the new shaft. I was able to just throw the bearing in the oven for about 30 minutes and it slipped right on.

It was at this point I realized I needed a new input shaft retainer. The old one wouldn't fit over the shaft haha. A new one is coming from summit and then I'll press a new race in and put it back together. For now I already got the top back on. Once that input retainer comes in and I throw the clutch on the engine the whole drivetrain will finally bolt together, Cummins to nv4500 to NP241.

Next I wanted to get the rear axle bolted up so that I'd have a rolling chassis again. This would make it much easier to roll around and position under the body to get the drivetrain positioning perfect. As a reminder I decided to use the dana 70 from the ram, so I guess I technically have a 1 ton rear axle in my explorer . I won't call the dana 50 in the front a "1 ton" since even though it came in f350's, I'm sure people will take issue with that haha.

First off I needed to cut off the old spring perches. Before I did anything though I shot a laser across the axle and marked a centerline in paint pen so I could keep the pinion angle right.

Then I took some measurements and figured out I need to move each perch in 2 1/8" so I marked that on the axle as well and started cutting. I was left with some gouges in the axle.

Filled those with some stick weld then ground it down. Threw the leaf spring perch back on, lined it up with the centerline and the mark left to right and tacked it on.

Once it was tacked on both sides I mocked it up under the explorer and everything fit. So I finished welded it out and threw some paint on it.

I didn't paint the whole thing since I do still need to do the shock mounts. However I can't do the shock mounts until I have the shocks I want for it so I can put everything in the right spot. I'll do the shocks front and rear at the same time later on.

For now I theoretically have a rolling chassis, except that I don't have enough tires for it and none of my wheels match . Other then that... Either way I've now got matching 8 lugs front and back on the chassis! Next up should hopefully be getting the drivetrain mocked up and the drivetrain mounts made. Then I'll figure out brakes and fuel, do the frame boxing, and the body should then be ready to put back on for good.

 

[Kiliona]

What's up with all the switches and gauges on the inside of it? Looks like it's got enough to outfit a fleet.








Showbox jiofi.local.html tplinklogin

Hmm.. I'm not sure, which picture or video are you looking at? Everythings stock on the inside of the explorer (so far) in that regard.

You might be looking at the stock radio which is real oldschool looking and has about 15 buttons just on that haha.

 

[Kiliona]

Anyone have any opinions on an unequal body lift?

Because the rear is now spring over axle (SOA) it's pretty high, but I do need about an inch of body lift in the front to clear the transmission. I'm not sure I want to raise the rear any more then it already is. My thought was I could add some inch spacers in the front, some 1/2" or 3/4" spacers in the middle (whatever I'd need to make it work), and no spacers in the rear and it might work to help level things a bit. I'll still need more work to get it completely level, but at least this way it would make things better and not worse haha.

I haven't thought of any downsides yet. Maybe that I'd have to keep it in mind when I eventually build rock sliders that they need to be slightly angled to the frame, other then that I don't see any reason not to. Anything I'm overlooking?

 

[dcgerard]

The only thing I can think of is maybe the toe and caster might go to far out for adjustment on the front end for a good alignment.

 

[Kiliona]

It's been a minute for an update. I've gotten the engine mounts done, transmission mount done, and the frame cleaned up and boxed. Here's some pictures.

I ended up putting the body back on for test fitting before I did the drivetrain mounts. Here's a picture of the massaging the firewall. I also made up a couple 1" spacers on my lathe. For now I'm going to try just running an unequal body lift, 1" front nothing in the rear, to try and get a little closer on the front height to the rear height since the rear is now spring over axle. The front will eventually get some lift springs as well once I get the suspension off my old explorer.

Here is basically the final engine test fit on where I planned to add the drivetrain mounts. I set the front clip on for reference. Notice on the left side of the image there's a couple inch gap between the fenders and the front clip. This is where some custom fenders/hood will be required. Also note this isn't necessary the final position of the front it's just sitting on the framerails for reference, the intercooler and radiator and such will change it's position.

Next I pulled the body back off so I could make the mounts easier and continue working on the frame. I cut the engine mounts out of the ram's frame to use and modified them to fit the chassis. These mounts got some more reinforcement later.

After this I needed to modify the motor mounts on the engine side. The engine essentially has 4 bolt holes in a rectangle shape, and uses 3 for the engine mount and 1 for some ground straps (I think later engines use all 4 for the motor mounts). I wanted to modify the mount so that I could move it up one set of bolt holes essentially so I welded some 1/4" plate on and drilled some holes in it to move the mount up, and the engine down. The mounts were cast steel so it took some postheat and preheat in the oven to make sure they didn't crack.

Finished and painted engine mounts:

Next I needed a transmission mount. I ended up taking a piece of 1/4" angle iron and cutting it up then welding the center section of the rams transmission crossmember to it. To mount it to the chassis I welded 3 nuts on either side to give me 6 grade 8 3/8" bolts holding it in. Here's the transmnission crossmember all painted up and installed (the washers were for setting the trans height to get the angle perfect, they'll be replaced with spacers I'll make on the lathe later).

Here's the drivetrain all bolted up into the chassis. As a reminder it's 12 valve 6BT cummins hooked up to a chevy nv4500 through an advance adapters bellhousing (since stock dodge bellhousings are expensive, doesn't actually "adapt" anything). The chevy nv4500 got a new input shaft to fit the diesel. Bolted to the 5 speed is an NP241DHD that also got a new input shaft to bolt up to the trans. Right now all of these are dry and there's no clutch installed just for mockup.

After this I wanted to freshen up the frame. No use going through all this work just to have an old rusty frame underneath it. I started by wirewheeling it down to bare metal.

I knew I wanted to box the middle section of the frame so next thing was to get it ready for that. My biggest concern was that the frame would rust from the inside out so I needed a way to make sure inside the frame stayed corrosion resistant. What I ended up doing was buying some weld through stainless steel spray paint (I bought seymour 216 stainless steel, rustoleum also sells one called steel tech and the big boy expensive one is called steel-it). After testing it I was reasonably confident that if I painted the inside of the frame, and then welded on the boxing plates that the paint would hold up on the inside and I wouldn't have corrosion issues. Here's the inside of the frame painted.

continued...

 

[Rick]

On its way to being the most reliable Ford diesel ever.

 

[Kiliona]

continued


After this I bought a sheet of 4'x8' 10 gauge steel from my local steel yard for ~$200. 10 gauge is about .14" thick which is between 1/8 and 3/16 and is almost the same thickness as the stock frame (about .157 IIRC, smaller then 3/16). I cut up some plates and boxed this middle section of the frame.

I also used this sheet to reinforce the motor mounts and also reinforce the section of the engine crossmember that I had to cut out forever ago to get the dana 50 front end to fit. Now the dana 50 fits under the engine crossmember completely and donesn't contact it before hitting the bump stops.

and now we're all up to date! As a reminder if you want to see this build in a different format you can checkout my youtube channel. My video on boxing the frame and such will be up Sunday!

https://www.youtube.com/channel/UCKUnyEZkcx_QBoYp3BjCyXQ

Next steps include painting the frame, running brake and fuel lines, reinstalling the fuel tank and modifying it to take the cummins pump/lines, and then getting the drivetrain installed permanently in the chassis.

 

[Kiliona]

Oh man, it's been a long time since an update. I absolutely haven't stopped working on it. No pictures since my elite explorer ran out, but let me talk through some stuff that's happened. If you want visuals you can check my youtube channel, otherwise here's the long list of what's been accomplished!

• I painted the frame
• I ordered some rough stuff shocks with like 10" stroke, and also bought some lift coils for an f150 and cut them to fit. The shocks haven't been installed but the coils have. The front will have way more travel than the rear at this point but I'll solve that later.
• I gutted the fuel pump assembly from the stock tank to use as a diesel pickup tube.
• Fuel lines were all ran using AN8 fuel line (first start with the engine on the frame!)
• Brake lines were all ran from the axles up to the frame where they'll eventually be connected to the master cylinder.
• I serviced the cummins, new clutch, rear main seal, front timing cover seal, Killer Dowel Pin fix, etc.
• Finally got the body on! This took cutting a huge hole for the transmission and then making a custom transmission tunnel cover that is welded on the back half near the T-case and the front is bolted up with threaded nut inserts.
• I got some wheels. Pro comp matte grey steel 17". I think the grey looks awesome on the white explorer. They are steel in case I want to later make them into bead locks. they are 17" to clear the brakes.
• I got some used tires. They're 37x12.5" pro comp extreme MT2's. I think they'll work well but it's a used pair with only like 20% tread in case the size doesn't work out, wanted to test it. They're 12.5 rather then something wider for clearance.
• I ran the hydraulic clutch for the manual transmisison. This took some modifying and welding up a new push rod for the master cylinder.
• I tore out the carpet and bed liner'd the floor on the interior. The carpet was in bad shape, it wouldn't quite fit the new transmission tunnel, and I prefer the bed liner so I don't have to worry about messing up the interior.
• The cummins is in the way of the steering box so I can not put a steering box in the stock location. I bought a new PS box for a 78-79 bronco which mounts on the outside of the frame.
• I made a steering setup with custom tie rod connectors. It turns out the passenger side tie rods are M22x1.5, and the driver side M20x1.5
• I did a tie rod flip (drilled out steering knuckle and put a tapered insert in) and while I was at it I went with GM 1 ton outer Tie Rod Ends for a small upgrade. These are 7/8"-18 so I had to make custom tie rod connectors with some 1/4" wall tubing and some metric weld in bungs from the UK. More trouble then it was worth probably, but originally I thought the GM TRE's would thread into the stock ford tie rod connetors. Turns out GM is SAE but I had already drilled out the knuckles for the steering flip which is why I needed the custom connectors. I also made the passenger side connector a couple inches longer than the driver side to somewhat account for the fact that the steering box is now on the exterior of the frame. This geometry is slightly off of stock, but with the combined tie rod flip and drop pitman arm the geometry is better then most lifted TTB's I see so I think it will work great!

This gets us up to the present. I am currently getting the ram radiator and intercooler installed (it'll fit I swear ) and at that point most of the major projects are done to get it running and driving. There's a bunch of small things that need done (wiring, shock mounts, gauges, lights, etc) but running and driving will be a huge miletstone. After that milestone will come some more large projects like actually getting fenders, hood, bumpers, rock sliders, lockers, etc.

 

[Rick]

I can't wait to hear the Explorer startup with the cackle of a 5.9 turbo diesel

 

[sandsprayer]

I can't wait to hear the Explorer startup with the cackle of a 5.9 turbo diesel

So glad to see this update.
Thought about this thread last week as I sat waiting for some heat to build in the Cummings.
Thanks @Kiliona

 

[92exp4x4]

This is awesome, i kinda forgot about this swap. Ill be going to YouTube in a bit.

 

[Travisfab]

Post some update pics!

 

[Josh P]

Great work, we NEED to see a video of it moving under it's own power when you get to that point.

 

[Kiliona]

I was able to get the cummins radiator and intercooler to fit, although it will take some modifications later to make a front end that works. I'm excited because this is super overkill on cooling with the stock mechanical fan and large radiator, but also it means I get to keep the MASSIVE intercooler that's basically larger than the stock explorer radiator was. It's also a nice form factor that can be removed all in one unit with a couple bolts and hoses giving me easy access to work on the engine.

I also got the explorer's throttle cable to adapt to the cummins by making an adapter on the lathe. I modified the explorers battery box, put it on the drivers side, and got some of the critical wiring done such as the fuel cutoff and starter. The fuel cutoff pull in coil is wired to the starter relay and the hold in coil is wired to what used to be the fuel pump relay. Since I don't need a fuel pump any more this works great and makes sure fuels on with the key on, and off with the key off. I also ran AN lines for the power steering to match the AN lines for the fuel.

So with the powertrain in, body on, critical wiring done, cooling system done, power steering system, etc all done that means....

FIRST REAL START VIDEO


It's now running, but not quite driving. I am currently working on getting the driveshafts in, mounting the front shocks, finishing up the brakes, etc and then I'll take it for the first short test drive up and down the street. After that it needs some body work and lights and such to make it a "little" more street legal. Finally after that, I'll start building the offroady stuff like bumpers, sliders, lockers, etc (just got a jd^2 tubing bender in that I'm pretty excited about).

BIG milestone!!! Hopefully more big milestones to come shortly

 

[Rick]

What a beast!

 

[sandsprayer]

What a beast!

Coming from a man who knows a beast when he sees one!
Digging on your well deserved sh** eating grin.

 

[boominXplorer]

Love it, lots of hard work there and plenty still to do. That fireup will probably help get the motivation to finish it up now.

 

[donalds]

Coming from a man who knows a beast when he sees one!
Digging on your well deserved sh** eating grin.

Me to I know that grinn