4Bts and M37s

[BobbyMike]

Can anyone who has done, or is doing, such a swap give more info on this? I know people have given out dribs and drabs, but I'm looking for a more centralized account of the swapp process.

I'm seriously considering buying one of the trucks from Dove.bid in one of the upcoming auction lot (wife has given ok to deal, very imporatnt step).

What other pieces would one need, adapters, etc?

Any hints, tips would be appreciated.

[CGarbee]

I can give you a pretty decent rundown if you need it, but please take a look at my website first...
www.garbee.net/~cabell

I've got a lot of info on my site covering my install of my 4BT in my M37...

[BobbyMike]

Duh, I feel stupid. Your site was one of the first M37 sites I ever looked at. I'll go back and look at some information I must have skipped over (as being irrelevant to my needs at the time).
Thanks!

[JimmieD]

Say, Cabell, I'm planning a swap into my Town Wagon also.

A BIG question was in choices of tranny/bellhousing. I saw some info on your site, but also stumbled into some elsewhere. A couple of guys have posted on other forums that the 6BT and 4BT have the same SAE bellhousing bolt pattern!! Further, any tranny/bell that works on a 6BT works on a 4BT. Well, I have an A-518 automatic and they were used on early 6BT, so, what do you say? Am I looking at a direct bolt-up or trouble in Dodge City?

JimmieD

[CGarbee]

They are the same familly of engine, made side by side in the same plants (one is just a short drive from me in Witikers, NC...), so, for any given version the parts swap back and forth...

For example, the first generation (12 valve, mechanical fuel injection versions) Dodge RAM parts bolt right onto the back of a first generation 4BT, and so forth.

For example, I am running a 1990 ReCon Cummins (factory rebuilt) 4BT taken out of an Entenmans Bakery Chevy P30 bread van. The current setup is: Dodge Flywheel from a 1994 Cummins RAM 4x4, aftermarket OEM style clutch for a 1994 Cummins RAM 4x4, Ford flywheel adapter from Roger at www.fordcummins.com (allows me to run a Ford specification transmission with a Dodge starter on the passenger side of the engine), aftermarket OEM style starter from a 1994 Cummins RAM, and a 1994 ZF S5-42 five speed overdrive transmission orginally fitted in a 1994 Ford F250HD 4x2. Clutch is hudraulic using the upgraded Ford 1994 Ford F250HD 4x2 slave cylinder and a Tilton remote reservoir MC utilizing the stock pedels.

The transmission uses Mercon for gear lube and if fully synchronized in all gears with a nice low first and a 0.76:1 fifth gear.

The point about mounting the starter to the passenger side is that it allows me to put the engine tight on the driver's side frame rail for maximum clearance of the front differential and to have a straight shot for the short driveshaft between the transmission and transfer case. The Dodge application fywheel adapter sticks the starter on the driver's side and it sticks out about seven inches from the side of the block... GM specifation flywheel adapter (as my engine originally had fitted) is a passenger side mount similar to what I currently am running.

My truck also has Lockrite Lockers and 4.89 gears in both ends. Have Michelin 900r16XZL's mounted on stock rims and Helitool disc brakes all the way around with a Chevy specification Bendix dual circuit MC.

I can run at 75mph all day long with a loaded truck and M101 trailer and get 17mpg on the Interstate... Of road performance is better than it was stock, as I just idle over a lot of obstructions but still have the ability to spin up the tires if I want to in mud...

Using the automatic setup from a RAM behind a 4BT wouldn't pose any problems, just strip everything off the back of the 6BT and bolt it onto the four banger...

I've got more info to plug onto my website as soon as I can find some time, so if you spot something that you'd like to know more about that is not on the website, ask and I'll post it here and will use my answers as a basis for future additions to my site...

Good luck to you both

[JimmieD]

Ooohhh, ooohhh GOOD NEWS! Thanks CG, it looks like I've got green lights all the way to Omaha.

I made a [hard] decision to stay with 2WD so this swap should be much easier. Motor mounts, radiator, fuel system, driveshaft, front springs should cover the engine install. Any suggestions on a radiator, as I currently run a 3 core desert type for the 360 so is that enough? I somehow doubt it, but....? Maybe get a 4 core soldered up?

Also I've got a 30 gallon poly saddle tank out of a '78 D200 I'm thinking of using. Any reason not to? I've read some about stock gasoline tank mods for diesel use, but thought I should ask. I can fab up a steel tank in the original location between frame rails in the rear, if I have time before the seasons change. Thanks.

[CGarbee]

I suspect that your radiator will be fine... Asside from the fact that the Cummins likes to run at 180-200F for optimum economy/performance (stock thermostat is 180F in the bread van engines), diesels as a general rule tend to run cooler than a similar displacement gasser and you are only talking 251 cu inches with the 3.9L (if my math is correct). The bread vans use the same radiator for the Cummins 4Bt and Chevy 350 powered trucks and I suspect the cooling requirements of a 350 and 360 are about the same...

Anyway, I am running a bone stock radiator in my M37 and have a radiator blanket on the truck and rarely turn on the electric cooling fan in the summer unless I'm in stop and roll traffic or sitting at idle somewhere, running the winch, etc... The bread vans use the same radiator for the Cummins 4Bt and Chevy 350 powered trucks...

As far as your tank, I think your fine with that as well. Only thing is that you will need to clean it out well (don't want either the residual gas or dirt in the system when you switch over) and add a fitting for your return fuel line (drill a hole near the current sender or fuel pickup location and use a brass elbow with a lock nut from the brake line fitting section of your local auto parts store and install it when you have the main pickup or sender out so that you can reach into the tank to hold the nut...). Plumb your return line using the same steel lines that you would use for your supply and you are all set...

Sounds like you are in good shape all around...

[Gordon Maney]

Mr. Garbee, this may seem odd, but have you ever looked at the availability of existing Cummins-fitted bracketry and compressors to allow air conditioning on your truck? Lots of street rods have air conditioning.

As I consider building such a truck for my main driver, since I have gotten soft in my old age, I like my air....

As part of such a conversion, I still think about lengthening the cab just a bit, to get more leg room.

How do you like that ZF transmission? How is the shift quality?

[JimmieD]

Thanks VERY much, CG, this is really beginning to sound good! It sounds as if it will actually be easier to swap in the 4BT than to do the mods/upgrades I was planning with a 360/A-518. Not only that, but the A-518 should live a lot longer behind the 4BT as they apparently did just fine behind 1st gen. 6BT's. I'm counting days in sweet anticipation!

Interesting idea of stretching the cab, Gordon! I assume you're speaking of punching out the firewal a bit forward; or are you looking at Club-cabbing it too? Looks like you're going to have to stretch the forum, too: Cabell, BobbyMike, Gordon, JimmieD and the rest of the 4BT guys will need a chit-chat spot?

Thanks for the help y'all....
JimmieD

[Gordon Maney]

Thanks VERY much, CG, this is really beginning to sound good! It sounds as if it will actually be easier to swap in the 4BT than to do the mods/upgrades I was planning with a 360/A-518. Not only that, but the A-518 should live a lot longer behind the 4BT as they apparently did just fine behind 1st gen. 6BT's. I'm counting days in sweet anticipation!

Interesting idea of stretching the cab, Gordon! I assume you're speaking of punching out the firewal a bit forward; or are you looking at Club-cabbing it too? Looks like you're going to have to stretch the forum, too: Cabell, BobbyMike, Gordon, JimmieD and the rest of the 4BT guys will need a chit-chat spot?

Thanks for the help y'all....
JimmieD

In simple terms, I mean increasing the dimension between the dash board and the back of the cab. Even just six or eight inches would be sufficient, allowing the seat to move farther back.

Early in the existence of these forums, I had a diesel forum. It really did not take off. I can easily add forums, but I don't want to add one if it draws only a small amount of traffic. This conversions forum works well for diesel conversions, and the 72-93 forum is suitable for those guys with original Cummins trucks. Thanks for the thought, however.

I would like to see more activity here regarding the Cummins conversions. I think the whole Frito truck frenzy that has emerged will really give this conversion approach some real energy. Although it might look a little funny, I think a person could buy one of those trucks and even drive it a while before you removed the engine.

[BobbyMike]

Thanks VERY much, CG, this is really beginning to sound good! It sounds as if it will actually be easier to swap in the 4BT than to do the mods/upgrades I was planning with a 360/A-518. Not only that, but the A-518 should live a lot longer behind the 4BT as they apparently did just fine behind 1st gen. 6BT's. I'm counting days in sweet anticipation!

Interesting idea of stretching the cab, Gordon! I assume you're speaking of punching out the firewal a bit forward; or are you looking at Club-cabbing it too? Looks like you're going to have to stretch the forum, too: Cabell, BobbyMike, Gordon, JimmieD and the rest of the 4BT guys will need a chit-chat spot?

Thanks for the help y'all....
JimmieD

Segregation? No, I like the melting pot effect! Part of my fun is reading all the threads, you never know when a bit of wisdom will pop up.

I'm going to probably buy a second truck so I can afford to take "Old Yeller" off the road for the operation. Problem is I recently spotted an old PW sitting in a farmer's field. Looks complete, don't know if it runs or not, but I'm really missing my '49 PW that I had to sell when we sold our farm.

I don't think my wife is ready for 3 trucks yet. ;(


AC in a PW, Gordon? That's a great idea, but since I'm still working on heat for my M37 I'll let you go first.

It's kinda like that old joke- When it was winter it was too cold to work on my truck and install the heater. Now that the weather's great I don't need it....

[JimmieD]

That sounds really neat to pop out the cab, Gordon! I've had more than one truck that needed it.

That was sorta tongue-in-cheek on the forums change. I'm with BobbyMike, I LOVE IT just the way it is! :~ )

[BobbyMike]

That sounds really neat to pop out the cab, Gordon! I've had more than one truck that needed it.

That was sorta tongue-in-cheek on the forums change. I'm with BobbyMike, I LOVE IT just the way it is! :~ )

I figured you were....

At 5'7" I never been cramped in any vehicle I've driven. In fact I once passed on a Mustang Mach 1 because I figured I'd need a stack of phone books to see over the hood. ;)

[JimmieD]

One of the dealerships I worked for also sold Datsuns, right at the time they changed from the Bluebird trucks to the 'later' 1600 designs. They caught on because of incredible mileage, excellent power and great handling and brakes. Problem was we had a lot of new trucks getting returned for a throttle pedal failure. The Japanese engineers, at an average height of 5' or so hadn't calculated in American numerical units. 6' 2" construction worker jumps in his Datsun after a few Colorado Koolaids after work and wants to get home to momma. The guys were punching the throttle pedals clear through the floor, leaving a gaping hole, 'cause of the short cabs and lightweight design!

There's not that much of me, BobbyMike, but I've tried to make it count sort of similar to your most excellent post in the 'Backroom' forum. Haven't replied there because you floored me with one punch.......!

JimmieD

[BobbyMike]

One of the dealerships I worked for also sold Datsuns, right at the time they changed from the Bluebird trucks to the 'later' 1600 designs. They caught on because of incredible mileage, excellent power and great handling and brakes. Problem was we had a lot of new trucks getting returned for a throttle pedal failure. The Japanese engineers, at an average height of 5' or so hadn't calculated in American numerical units. 6' 2" construction worker jumps in his Datsun after a few Colorado Koolaids after work and wants to get home to momma. The guys were punching the throttle pedals clear through the floor, leaving a gaping hole, 'cause of the short cabs and lightweight design!

There's not that much of me, BobbyMike, but I've tried to make it count sort of similar to your most excellent post in the 'Backroom' forum. Haven't replied there because you floored me with one punch.......!

JimmieD

Aw shucks!
Thanks for the kind words.

[warlock440]

Thanks VERY much, CG, this is really beginning to sound good! It sounds as if it will actually be easier to swap in the 4BT than to do the mods/upgrades I was planning with a 360/A-518. Not only that, but the A-518 should live a lot longer behind the 4BT as they apparently did just fine behind 1st gen. 6BT's. I'm counting days in sweet anticipation!

JimmieD


If you are thinking about using an A518 from behind a gas engine on a Cummins it will not work.. The tranny for the Diesel has a different bellhousing than the gasoline version..I also believe the diesel tranny has more and heavier duty clutches..Torque converters are also different with the diesel having a lower stall speed to take advantage of the diesels low RPM torque producing ability..

[JimmieD]

Hmmmm....I was figuring on a different converter, but wasn't figuring on a difference between A-518 bells! This tranny is a HD unit so it should be good on clutches. That would be a real bummer on bellhousing difference. Got any links where I can get more info on this? Any ideas about adapters?

JimmieD

[warlock440]

Probably try the turbo diesel registry..

[JimmieD]

I posted over at Diesel truck resource and got a similar answer, Warlock440. Fella sid tranny bellhousings are different. But, he also said all A-518's behind a 6BT need an adapter plate to make it work, and to check with Cummins to find out if they make one for the tranny I have.

Other possibilties: get ahold of the Cummins A-518 adapter and:

1] See if the Cummins adapter plate can be drilled to bolt to 360 trans
2] Use it for a pattern to custom cut my own adapter plate
3] Forget the whole thing, sell this A-518 and get the right one....?

I'm wondering if the 4BT and 6Bt use the SAE 3 bellhousing pattern, anybody know? I got the spec. sheet off of your site, Cabell, but didn't see which SAE Bellhousing fits 4BT's. Don't know if I missed it or it wasn't there.

[Russ Erickson]

A while back, I took a bellhousing from a '90 Dodge CTD with Getrag 5-speed and set it against the back of an IHC 345 c.i. V-8. Four of the bolt holes were a perfect match between the bellhousing and the back of the IHC engine. The Getrag bellhousing was made for a driver's side starter and the IHC engine had a passenger's side starter, and this is why the rest of the holes failed to match. The bottom line here is that there are literally thousands of IHC bellhousings available, and they are set up for passenger side starters. Some enterprising feller (CG?? or Charles Talbert??) probably could make it work with a 4BT engine.

[warlock440]

[QUOTE=JimmieD] A-518's behind a 6BT need an adapter plate to make it work,[QUOTE]

All Cummins require an "adapter" Also known as a Flywheel housing The only ones I know of are the SAE sizes, one for the chevy bellhousing, and the Dodge pattern which is specific to the Cummins.. If they had to cast a special block for each application it would be an inventory nightmare as well as having to have several different core castings.. By making all the engine blocks the same they can keep inventory down and and put engine parts for the desired application on as the engine comes down the assembly line..


[QUOTE=JimmieD] Other possibilties: get ahold of the Cummins A-518 adapter and:

1] See if the Cummins adapter plate can be drilled to bolt to 360 trans[QUOTE]

I do not believe there is enough material for this as the V8 bellhopusing is smaller than the cummins



[QUOTE=JimmieD]2] Use it for a pattern to custom cut my own adapter plate[QUOTE]]

That might work as I believe that is what fordcummins does for the kit for putting the Cummins in Fords


[QUOTE=JimmieD]3] Forget the whole thing, sell this A-518 and get the right one....?[QUOTE]

This is in my opinion the best option..

[JimmieD]

Thanks for the help, Warlock440.

Just like many other vintage Dodge owners I want to keep the truck 'ALL DODGE!' but tranny's are kind of the wild card in swaps. I'm rethinking the 4BT install.

I'll be buying a breadtruck and it will have a transmission behind the engine with all of the parts spec'd by engineers to perform in service under loads. For the most part all of the manufacturers make decent transmissions. If they're not reliable or strong enough there's aftermarket parts for any of them to take them to higher levels of performance. Based on that I'm now thinking it most practical and realistic and a whole lot less time, money and hassles to simply stuff in whatever I end up with. Currently I have very little time to complete the install so this solves loads of problems in the short term.

That would give me a running rig right away, and at a later date I can assemble needed pieces to make it 'ALL DODGE!' once again if I'm having trouble sleeping.

JimmieD

[BobbyMike]

Thanks for the help, Warlock440.

Just like many other vintage Dodge owners I want to keep the truck 'ALL DODGE!' but tranny's are kind of the wild card in swaps. I'm rethinking the 4BT install.

I'll be buying a breadtruck and it will have a transmission behind the engine with all of the parts spec'd by engineers to perform in service under loads. For the most part all of the manufacturers make decent transmissions. If they're not reliable or strong enough there's aftermarket parts for any of them to take them to higher levels of performance. Based on that I'm now thinking it most practical and realistic and a whole lot less time, money and hassles to simply stuff in whatever I end up with. Currently I have very little time to complete the install so this solves loads of problems in the short term.

That would give me a running rig right away, and at a later date I can assemble needed pieces to make it 'ALL DODGE!' once again if I'm having trouble sleeping.

JimmieD

As I'm no Charles Talbert, or Cabell Garbee I'll probably go a similar route.

Looks like I'm going to have to tackle that new shop soon!

[CGarbee]

To answer a couple of questions in some of the posts since I was last visiting...

I have looked at adding AC and such to my truck using the Cummins brackets... One can also use the parts off a Dodge RAM and do the same thing... Very easy to do and Lee Alessi down in Baton Rouge is the one to really talk about it as he put AC on the 4BT that he had in his M715 and will be installing it on his 4BT powered Carryall... On-board air and powersteering are also easy to add as they are gear driven from the from the timing gear assembly... All you do is get your parts manual and cozy up to the counter at your local Cummins shop (my favorite, incidently, is not my local Cummins distributor but my local Komatsu dealer--closer to my office and very good folks behind the counter...). Or, just spend some time at the wrecking yards.

The flywheel adapters available from Cummins for the 4BT are the current Dodge pattern for the NV4500/4600 and the SAE#3. Last time I talked to my Cummins distributor, they couldn't find a Chevy or Ford pattern in Cummins parts locator, but you can get the Chevy or Ford pattern off the bread van engines since that was their application...and another Cummins shop might have better luck finding one... Roger at FordCummins makes a slick flywheel adapter that allows for the use of a Ford transmission (such as the ZF that I use) with the Dodge specification starter and clutch setup.

I really like the ZF. Extemely smooth shifting, high torque rating (420lb-ft for the S5-42 and 470lb-ft for the S5-47...), innexpensive compared to others in it's class, and it uses Mercon for lube (easy to find and innexpensive, especially when compared to the stuff specified for the New Venture transmissions...). Has a pair of SAE six bolt PTO covers (one on each side) so putting a Chelsea or Muncie PTO on them is a snap...

[JimmieD]

Thanks for the additional info, that's most helpful!

JimmieD

[BobbyMike]

I really appreciate everybody who's contributed to this thread taking the time to do so. It's all been very helpful to me in my decision making.

Don't think I'll be getting a 4BT at the May Dovebid auction as the nearest sites are way over by Philly, but there's another auction in June. That gives me time to figure out what I'll do with the breadtruck.

[CGarbee]

Best use for your donor breadtruck (as long as you don't want it sitting in the back forty as a tool shed or chicken coop, etc.) is to haul it off (or have it hauled off) to the scrap yard. You've got a nice heavy steel frame and either a steel or (more commonly) aluminum body... Metal prices being what they are, you can do pretty well on the metal...
The other parts such as the axles, radiator, etc. are worth something at the auto scrap yards or by listing them in local sales papers, but it's easier to let them go with the frame and body to the metal processor...
Remember, you can cut the exhaust pipe that was on the donor truck and use the muffler and the pipe on your PW to keep the noise down to a comfortable level, so don't scrap that system until everything is looking, sounding, and running good in your project...

Good luck.

[BobbyMike]

Thanks Cabell, that's the kind of advice that's nice to have before hand. I have 3 acres, but have limited access to most of it for something that big. I'll have to figure where to keep the breadtruck for awhile, probably be able to use my nieghbors drive for access if I bribe him with enough fresh eggs.