FFPW 6BT Diesel Conversion/Body Swap

[bbarry]

I'm new to this forum and have enjoyed reading back through many of the postings here. I'm curious whether anyone here has heard of any attempts to mount a PowerWagon body on a diesel Dodge Ram frame. It seems to me that using a rolling chassis/eng/trans combo from a 1T Ram would eliminate many of the issues with finding mating parts, matching trans to axle ratios, etc. Fabricating new body mounts would have to be simpler, right?

I see a fair amount of conversation about 4BT conversions...I wonder if the fenders, hood and firewall could be made to squeeze around the 6BT in the Ram frame?

I'm curious to see what everyone thinks...

Brad

[HWooldridge]

I certainly have not made any measurements but I suspect the newer Dodge rolling chassis will not easily fit under an M37 or civvy PW body. The engine swaps are probably the easier way to get a modern powerplant. Maybe someone will chime in but that's my gut feeling.

[JimmieD]

I think you'll find that there are insurmountable problems fitting the 6BT components in the FFPW dimensions. The 3.9 4BT is only about 24" long, where the 5.9 6BTA is nearly 33% longer, around 34-36". Also the big Dodge is usually intercooled and it's hard enough fitting the intercooler parts in an early non-intercooled Ram. The FFPW doesn't offer much width for a massive radiator and intercooler so the dimensions must be translated to fore and aft fitments using non-stock components. You would probably end up with more headaches trying to adapt the chassis and needed accessories to the FFPW body than you would with an engine swap. Overall I don't think the 6BT powerplant will fit in a FFPW.

The 4BT is chosen because of its conservative dimensions and lighter weight but even then it can be a fairly close fit. The main parts needed for a 4BT swap are the engine, bellhousing adapter, bellhousing and one of several transmissions, with much less radiator required to cool the powerplant. Many choices of transmissions and ratios are available for the Cummins 4BT, as any 6BT tranny including GM versions will bolt to the proper Cummins bellhousing. That is, Dodge 727 Torqueflite, A-518, A-618, NV4500, Getrag 6 speed,
TH400, SM465, Allison etc.

[Sickcall]

Jimmie, could I use a spicer 3053A behind the 4bt? Not looking to do a custom bell housing, what available?

Thanks

[JimmieD]

Hey S/C!

This is the guy to ask, not me:

http://www.garbee.net/~cabell/transmission.htm

Very nice fella and I'm sure he'd be happy to assist you in your choices. He's done 4BT conversion on military trucks before. I don't know about the specific bellhousings available, only that once you have the Cummins/Dodge adapter plate the Dodge trannies will bolt right up. Hey may have info on SAE bolt patterns etc. There's always issues regarding input shaft diameter, spline count, and length in combination with a correct clutch. I'm using a '98 W-350 Cummins flywheel with a '96 Cummins NV4500 and all Dodge clutch components from South Bend. Less hassles, 4 gears plus overdrive, smooth synchromeshed shifts, and fat and lazy 5th.

Also my Town Wagon I'm converting is a 2WD so no info on specifics on 4WD military here. I was going to install the complete drivetrain out of my '90 W-350 behind the 4BT, Dana 70/Dana 60/NP205 but decided I wanted simpler components and 2 WD for now.

JimmieD

[CGarbee]

A Spicer 3053A is perhaps the easiest transmission to put behind a 4BT... Use the SAE#3 flywheel adapter that Cummins offers as a "standard" option and the transmission bolts right up using standard SAE components... It is the transmission that Charles Talbert at M-Series Rebuild uses behind the engines that he installs.

I have info on the Spicer 3053A on my website, as well as SAE bellhousing dimension information...

Nice thing about the Cummins SAE flywheel adapter is that it is drilled for two motor mounts, so you can use a pair off the flywheel adapter in combination with the industrial single point yoke mount on the front of the engine for a nice three point mounting...

I have talked to a couple of folks recently about doing conversions who were a little hesitant to use the Spicer since it does have a shift pattern that is not "standard" for a modern five speed (of course, it isn't a modern five speed, just a very robust, innexpensive, good one). For them I suggested a ZF five speed. I've become very partial to the ZF S5-42 that was used behind the Powerstroke in F250-350 HD models a few years back. It is a very robust five speed with a little more OD capability than the Spicer 3053A and it can be mounted using an adapter from FordCummins that allows for the use of the Dodge starter, clutch, and flywheel (although the starter is moved to the passenger side of the engine--helping out with engine placement...).

I know some folks really like the NV4500 that was used behind the Cummins six cylinder engines in the RAM trucks, but they are pricey, and when you put the Dodge starter on the driver's side (stock location for the Dodge application), it sticks way out from the engine forcing you to mount the engine closer to the front differential than I personally like... I've got some info about these on my website as well, but Paul in NY has more experience with them than I since he has used them in two projects...

Ask away...

[Sickcall]

Cabell,

I am interested in the parts under the BH. Maybe a list of what I need to make a clean and no hassle bolt up. Do I use a stock 4BT flywheel with the cluth and pressure plate from a Duece, hydraulic or mechanical? I would like to start accumulating the necessary parts in preperation.

Thanks

[MoparNorm]

Cabell,
What's the secret to getting the ZF S5-42 to shift decent? Or is it just a function of the design that you have to live with the long throws and large gaps between gears? Are there aftermarket ratios to "tighten" up the spacing between gears?
Thanks
MN

[CGarbee]

Sickcall,
You have to use a Cummins SAE flywheel... It is a stock item. After that, you can use the M35 parts as they are all SAE standard.
MoparNorm,
The throw of my ZF feels right to me, but I sorta think that a truck should have a longer through than my car... It isn't near as long as the Spicer 3053A in my M35's... As far as gear ratios, I think that there are three or four sets available for the S5-42. One is for smallblock, one for bigblock, one for diesel... They have different first gears, the same fifth gear, and the ones in between get adjusted accordingly... I'll have to pull out some books to get actual ratios for you...

OK, a little "Googling" gives us:
ZF S5-42
 Vehicle: 1987-1995 F250, F350, Super Duty
 Gear Ratio: Wide Ratio Gasoline/Diesel
1st gear = 5.72
2nd gear = 2.94
3rd gear = 1.61
4th gear = 1.0
5th gear = 0.76
Reverse = 5.24
 Gear Ratio: Close Ratio Diesel
1st gear = 4.14
2nd gear = 2.37
3rd gear = 1.42
4th gear = 1.0
5th gear = 0.77
Reverse = 3.79

I'm pretty sure that there is a least one more version in European service, but I didn't see a reference to it on the sites that I was looking at. i do know that the Chelsea PTO catalog list three different versions of the transmission (the ZF has a 6 bolt SAE port on both sides of the case...).

One other thing about the ZF, it uses Mercon and not a heavyweight gear oil... I am currently using MerconIII in mine (was cheap and on the shelf...). The Spicer 3053A uses 90wt (make sure that you use GL1 or a GL5-MT1 as you need a gear lube that is safe for yellow metal)

[MoparNorm]

Thanks!
I test drove one when I was buying my work fleet back in 1988. I thought it was awkward at the time (when compared to a 435) because of the length of throws and the amount of pressure required to move the shifter. It seemed like the over drive was about a 3 foot throw...= ) It could have been because of the tightness (new) of the trans, since the NV5600 is hard to shift at first also, but losens up after about 5,000 miles. It was enough of a deterrent that I opted for C6 transmissions instead. Our traffic out here is no place for a stick anyway, at rush hour.
Thanks for looking that up for me, I believe it's a direct bolt up to the 7.3.
MN

[yosemitesamiam]

I'm curious whether anyone here has heard of any attempts to mount a PowerWagon body on a diesel Dodge Ram frame. It seems to me that using a rolling chassis/eng/trans combo from a 1T Ram would eliminate many of the issues with finding mating parts, matching trans to axle ratios, etc. Fabricating new body mounts would have to be simpler, right?

I'm curious to see what everyone thinks...

Brad

That has been my #1 curiosity since starting my search for a restorable 1957 or so Civilian m-37. I know the truck is an 8' bed and has a 126" wheelbase. In retrospect....a Dodge Ram with 12V CTD came in roughly 135" wheelbase at its smallest, this being the 1994 to 2001 newer chasis. I have no idea on the width of an m-37...anyone care to share?

[squatch]

mag truck

As I recall last yr one of the 4x4 mags had a short article on a PW widow panel that had been put on a late diesel chassis for an outdoor photographer. I believe it was done by a pro shop in Texas. Lots of work and money.

[yosemitesamiam]

As I recall last yr one of the 4x4 mags had a short article on a PW widow panel that had been put on a late diesel chassis for an outdoor photographer. I believe it was done by a pro shop in Texas. Lots of work and money.

Interesting! I'd assume it would be a lot more labor than doing the entire driveline....4BT, NV4500, Klune-V t-case, and custom axles and drivelines.

How are the frames on these old trucks? Not as weak as the 1988 Dodge Ram chasis I hope! I would hate to drop a high output 4BT in there only to find out it is folding up the frame like the 6BTs did to those first Rams they came in.

Lastly...axles. Are you guys who are doing the swap having to customize axles? Anyone tried Portals? http://www.killeraxles.com/html/portal_axles.html

Thanks guys...I'm really considering this project with a PW when I do get my hands on one. My wife is going to kill me, but ...she will get over it.

[JimmieD]

Interesting! I'd assume it would be a lot more labor than doing the entire driveline....4BT, NV4500, Klune-V t-case, and custom axles and drivelines.

How are the frames on these old trucks? Not as weak as the 1988 Dodge Ram chasis I hope! I would hate to drop a high output 4BT in there only to find out it is folding up the frame like the 6BTs did to those first Rams they came in.

Lastly...axles. Are you guys who are doing the swap having to customize axles? Anyone tried Portals? http://www.killeraxles.com/html/portal_axles.html

Thanks guys...I'm really considering this project with a PW when I do get my hands on one. My wife is going to kill me, but ****...she will get over it.

Hmmm....sounds like you've been visiting too many Ferd or Shove-Me forums! I hang out on Dodge Cummins forums and have yet to hear of a single frame 'folding up' as you say, or of any frame problems whatsoever. What I do hear is guys using stock 1st Gen trucks with some pump tweaks pulling 25K to 35K loads, NO PROBLEM! The only known frame problem is some cracking around the steering gear box on a few trucks, and that's not that common at all. I'd check the sources on that info as I think someone's pretty confused....

[yosemitesamiam]

Hmmm....sounds like you've been visiting too many Ferd or Shove-Me forums! I hang out on Dodge Cummins forums and have yet to hear of a single frame 'folding up' as you say, or of any frame problems whatsoever. What I do hear is guys using stock 1st Gen trucks with some pump tweaks pulling 25K to 35K loads, NO PROBLEM! The only known frame problem is some cracking around the steering gear box on a few trucks, and that's not that common at all. I'd check the sources on that info as I think someone's pretty confused....

LOL! No, just LandBoozer. :) I will do that. Not that it will matter much...I think a body swap would be terribly difficult, was just curious to bring the matter back up and see if it had been done!

I found a military m-37 for sale, guy put a 5.9 CTD in it. Don't know how, waiting on pix. It is a beautiful piece of machinary. He wants $15K for it. I don't think I'm too into it as I'm really looking for a civilian style PW...ya know...rounded roof, etc.

Anyway..."hi ho, hi ho...off to work I go." Someone has to fund my habit.

Sam