My tow pig/DD build thread. F350/Cummins 6.7/twins/6R140

Hotrodtractor

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Unfortunately, you can only go so far in that regard before you need to rip out the 6.4 and start testing the 6.7 and 6R140 in the truck.

I think I'm there. But there is no way to anticipate what I might encounter.

i might be calling on people with an '08 to '11 and Auto Enginuity to watch PIDs for me if I run into trouble after my truck becomes "incapacitated".

Let me state it up front, this swap is a bit of a gamble as far as the transmission selection goes. I think the engine part is fine. If the transmission doesn't doesn't work out, I'll fall back to a different model.

I might even go so far as to recommend testing whatever controller you intend on using on an actual truck. I agree its a gamble - but you also have a whole lot of what you need in that picture I posted - combine that with an actual truck to get signals off of and being able to figure out how and when to apply which solenoids and do it so it doesn't "lock up" the trans is going to make or break the transmission selection.
 

me2

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this is one hell of a project! looking forward to seeing how it turns out.
I'm surprised that nobody has done it before. The GVWR on my F350 is 11,500 pounds. As close as you can get to a dually without having one. That is a big plus for me. The GVWR on my old truck was 8800 pounds ! It handled the trailer well, but its time to move up a bit.

FWIW, my old truck had air ride suspension, front and back. My F350 will be getting the same, in due time.
 

me2

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I'm getting lots of questions, so rather than answer them individually, I will answer them here.

What ECM am I using ?

Its a CM2100 from an 08 truck. This engine originally came with a CM2200 ECM, but EFI Live doesn't handle those yet, so I'll use the CM2100 ECM until then.

How do I wire the ECM into the truck ?

The CM2100 ECMs have 2 connectors. One handles all the engine connections, like sensors, injectors and those sorts of things.

The other connector is the "OEM" stuff, ie the truck builder. This is usually Dodge, Freightliner, etc., but in this case its where I connect the engine to my truck.

My local Cummins dealer got me a connector ($55) and pins to plug into the OEM port. The OEM and engine ports look the same, but they are keyed differently. I think the Engine port has a "5" key and the OEM port has a "6" key. If you are ordering one and need to know, if you look into the connector beside the key you can see it printed there.

Having separate OEM and Engine ports on the ECM is new. When I wired my 5.9 into old truck, the engine wiring harness itself had a connector (C130) which was where everything connected in.

Does the ECM need anything from the Dodge truck to run the engine ?

No, sort of.

Technically the Dodge Cummins engines are a complete stand alone unit with their ECM. However, some trucks have a security system in them, ie a SKIM (module) and when it is supposed to be there and isn't, the ECM shuts down the engine after it has run for 10 seconds.

Luckily this functionality can be disabled with EFI Live. And I'll be doing that if my ECMs have it enabled.

Other than a SKIM, all the engine needs are power to the correct pins and an accelerator (throttle) signal. There are a number of ways to do the throttle signal, one of which is to use a Dodge accelerator pedal assembly. For various reasons I will not be doing that.

How are you going to get the Ford transmission controller to talk to the Cummins engine ?

There are 2 answers to this question.

Answer 1) I'm not going to use the Ford transmission controller. I am going to use a custom controller.

I am doing this because I want the transmission to do some things that the Ford controller doesn't support. I'll get into this later in the swap.

2) I think its pretty feasible to get the Ford transmission controller to work behind the Cummins engine. I've taken a really good look at the schematics for the 2011 Fords and basically its just a matter of sending the right CAN messages to the Ford controller and it would work.

Having said that, the message formats used by the Cummins(Dodge) ECM and the Ford ECM are different. It does not appear that Ford supports the J1939 format, whereas the Cummins (Dodge) ECM has a mixture of J1939 and proprietary formats.

However, even though the formats are different, the necessary data appears to be all there.

However, one can build a microcontroller that sits between the Cummins engine and the Ford transmission controller that gets the data the TC needs from the ECM and converts it into the Ford format and sends it to the ECM.

So it is very possible to do this swap using the Ford TC.

I've heard that Ford is having trouble with the 6R140. Why are you using it in a swap ?

Ford is having shift calibration issues with the 6R140. Under certain conditions some of the solenoids are shifting some of the clutches sooner or later than they should be, which is leading to missed shifts or shift flare.

Because I am using a custom TC and tuning it myself, I should be able to tune around any shift calibrations issues that Ford may be having.

Will your truck be emissions compliant ?

I'm not an expert, but most jurisdictions allow an engine swap provided the new engine is the same emissions age or new than the old one.

The Cummins 6.7 is emissions certified until 2012. My specific engine was used in a MY 2010 truck. My truck is a MY2008.

If my Cummins 6.7 was equipped with all its emissions equipment, my truck would have no problem passing an emissions test anywhere in the country.

Obviously the twin turbo setup negates passing the emissions test in some jurisdictions. But nothing stops me from putting the engine back to stock should I need to.

I will be deleting the EGR and DPF for the time being. I may install them at a later date.

FWIW, I could also have probably swapped in a MY2007.5 Cummins 5.9 into my truck, its an early Job 1 truck. However, it would probably be a lot easier to convince an inspector that the swap is compliant if the new engine (6.7) has a DPF like the old on (6.4) did.

How am I going to handle the OBDII scanning ?

My truck will have 2 OBDII scan ports. One for the chassis and the other for the engine.

The Ford ECM will stay installed in my truck as it is needed to handle certain dash and body functions. It would be a big job to remove it and replace it with a custom "body" computer.

There were a bunch of mechanical questions too, but I'll answer them as we go because pictures will make it apparent what I am doing. Pictures don't tell much of a story when it comes to wiring and software.
 
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me2

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Why am I not using an Allison ?

I am going to address this question once because it was asked. I don't want to start a debate on it. Everyone has their favorite components. I might be right, I might be wrong, bottom line is I am going to try the 6R140. If its a dud, I'll swap it out.

Cost.

A stock 6 speed Allison transmission will not hold 1100 ftlbs, especially in a towing application. The stock OD clutch packs are notorious for failing in towing applications.

I don't mean that statement as an insult to the transmission or anyone who owns one. I arrived at that conclusion by spending about a week of my spare time on Duramax forums and reading about transmission failures. I did the same sort of reading on Ford and Dodge forums.

A 6 speed Allison transmission core is $2500. A high performance rebuild is about $5K. Total transmission cost, about $7500.

I think a stock 6R140 will hold 1100 ftlbs in a towing application. Its a new transmission. I might be right, I might be wrong.

From what I can tell the 5R110 does better than any other stock auto transmission with tuned engines. I think the 6R140 takes that strength a step further and adds another gear ratio.

For those that aren't aware, the 6R140 was a clean sheet design. Its totally new with zero carry over from the 5R110.

The "140" part of the name means its designed to handle 1400 ftlbs of torque on the transmission input shaft. With a TC ratio of 1.8, that is roughly 800 ftlbs at the engine, but with the TC locked, that is a full 1400 ftlbs from the engine. And that is with stock clutch pack application pressures.

I paid $2450 for my 6R140 with the torque converter, with less than 10K on it.

I'll be using the stock TC as well.

Gear Ratios

The gear ratios in the Allison are 3.1, 1.81, 1.41, 1.0, 0.71 and 0.61.
The gear ratios in the 6R140 are 3.97, 2.32, 1.52, 1.15, 0.86 and 0.67
The top 2 gear ratios in a ZF6 are 1.0 and 0.72.

My old truck has the same axle ratios and tires as my new truck.

With the ZF6 in OD (0.72), the engine is running 1650 RPM at 60MPH. That is not a good gear for towing, although the stock 5.9 will tow our trailer there unless we are climbing a significant grade or have a very strong headwind.

The next gear down on the ZF is direct, which works for towing, but the engine is running about 2300 RPM at 60 MPH, where its noisier and thirstier. Engine speed is about 2450 at 65 MPH.

With the Allison transmission, towing in OD (0.61) is pretty much out of the question, especially given the issues people have with the OD clutch pack.

The next gear down is 0.71, which is just about the same as OD in the ZF6 I have now. That gear will work, but its not optimal.

The next gear down from that is direct, which is the same as in the ZF6.

So a 6 speed Allison basically gives me the same gear ratios for towing that I had with the ZF6, with the addition of another OD gear for running empty.

What I really want is a double OD transmission with 2 usable OD gears for towing. Enter the 6R140.

OD is 0.67 in the 6R140, which is about 1550 RPM at 60 MPH and 1650 RPM at 65 MPH. In easy towing conditions, a torquey 6.7 can probably pull the trailer in that gear and it should result in very good fuel economy. Edit. My dad has a smaller 5er than we do. His truck has a taller axle ratio (3.31 ?) but he doesn't have 20" wheels and he pulls his trailer in OD all the time.

When the load gets too heavy, one gear down is 0.86, which is 1970 RPM at 60 MPH and 2134 RPM at 65 MPH. I think that is almost the perfect engine speed for towing. Its 400 RPM less than a direct gear.

The next gear down on the 6R140 is 1.15:1, which is a little bigger split than I'd like but still a very usable gear. It puts the engine right into its powerband at 2650 RPM at 60 MPH. If my engine plans work out, my engine makes nearly 600 HP at the crank there. Should be a perfect gear for pulling steep passes at 50 MPH, which is 2200 RPM. I expect my engine to make 500 HP (1200 ftlbs) at the crank at 2200 RPM.

There are other misc reasons as well, such as the Ford column shifter works (mechanically) directly with the 6R140 with no modifications. Or at least it appears to.

The devil is in the details. I'll share what I learn, right or wrong, going forward.
 
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me2

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Here is a table of Allison transmission ratings from their 2010 brochure.

Allison%2520transmission%2520specs.jpg


As you can see, the maximum input shaft (turbine) torque rating of these transmissions is 950 ftbls. Versus the 1400 ftlbs for the 6R140.

I'm sure that someone might chime in and tell me that the rating on the Allison used in the GM trucks is higher. And it probably is. But I can't help but feeling that the Allison has less strength reserve to deal with the torque my engine will make than the 6R140.

I'm also sure that there are many successful drag racing and pulling trucks running Allisons. Trailer towing is entirely different than drag racing or truck pulling. When pulling trailers the transmission clutches must hold the torque for hours at a time without slipping.
 
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Hotrodtractor

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Not wanting to start an argument or question your decision - but I tow very heavy (I plead the 5th heavy...) with my Allison in my Dmax - the Dmax is rocking about 420hp in the tow tune with compounds - it is a super nice flat power curve - and I basically never leave 6th gear while on the interstate. Occasionally I will drop it down to 5th only to counteract a current tuning problem I have where my CP3 literally can not supply enough fuel volume to maintain the injection pressure and PW I am need to maintain speed at a low RPM. Yes - my transmission is "built" with an off the shelf set of parts in a common kit - but the kit cost is sub $3K - the Allison 6 speed trans I bought for my project out of a junkyard guaranteed good for $1K delivered - and I have the benefit of an almost plug and play Allison computer and harness unless I want to figure out how to enable torque limiting on my swap. So that would put you at $4K ish. Plus you could have the benefit of getting an Allison 1000 with an SAE bellhousing and an off the shelf SAE bellhousing adapter for the Cummins and bolt them together for significantly cheaper than custom making an adapter.

Again - I want to see the 6R work - I think its cool - but I felt I needed to add a little different perspective as I think its really a wash at the end of the day on which transmission you choose because each has their own unique set of headaches that need conquered, but the the Allison has people that has been there and conquered them before. Good luck and I hope the journey through this project is smooth as possible for you.
 

Denver

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The 6.7 comes in the F650's. Wouldn't it be easier to pull the electronics from a F650 vs. a Dodge?
 

TrailerHauler

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I'm very glad you decided to put this up here, so far I've already learned a few things, and its been a great read! I am really looking forward to seeing the progression of this swap over the next month or so, not to mention someone trying something different! Everything looks great so far, and hopefully things go smoothly and as planned.
 

me2

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The 6.7 comes in the F650's. Wouldn't it be easier to pull the electronics from a F650 vs. a Dodge?
I don't see any advantage.

Some or all of the non Dodge 6.7s use DEF and I don't want any part of that.

The non DEF engines have the same engine wiring from what I can tell by looking in Cummins Quickserve. On those engines only the ECM is different between them and the Dodge application.

The highest power rating that I know of for vehicle based 6.7s is the motorhome RV 6.7 which is rated at 360/800. I think they called it the ISB XT 6.7.

EFI Live does not work with non Dodge ECMs. Thus there is no way to turn off the EGR, DPF, etc, or change the fuel delivery. That particular engine is paired with an Allison 3000 transmission, so I am not sure how it would work as a stand alone engine.
 

me2

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Transmission Adapter

People keep talking about the trouble and cost of making the transmission adapter plate. It really isn't a big deal.

The 6R140 uses an SAE #2 type bellhousing.

By type, I mean that it has the usual 12 holes equally spaced around the circle like a regular SAE #2 bellhousing, EXCEPT that the hole by the starter is out of position and there are a couple alignment dowels that aren't on a usual SAE #2 bellhousing, instead of the alignment lip that is on some.

I made the transmission adapter plate for the swap (5.9 CR and ZF6) on my old truck. The transmission pattern for the 7.3 ZF6* is much harder to set up than the transmission pattern for the 6R140. The block pattern is the same for the 5.9CR and the 6.7 CR and I still have my CAD files, so it shouldn't be very difficult to figure out the adapter plate geometry.

However, there are a couple snags.

Snag #1 is that I don't have the flex plate figured out yet and you need to get the flex plate depth correct before you make the transmission adapter plate.

The stock Dodge Cummins flex plates have been known to fail with increased power. They are out of the question.

The Ford flex plates seem to be fairly stout. But the center diameter and bolt pattern from the Ford 6.7 don't match the crankshaft pattern on the Cummins 6.7, so its not a simple bolt on. As a matter of fact, the Ford flex plate uses 10 bolts and the Cummins uses 8 bolts.

And there is a flexplate depth spacing issue as well.

I haven't figured out what I am doing to do about this yet. Options include machining my own flexplate, buying an aftermarket Cummins flexplate or making an adapter to mount the Ford flex plate to the Cummins crankshaft.

Snag #2 is that Ford puts the starter on the passenger side and I hate it there. Dodge puts it on the driver's side where I like it, but with the ZF6 that meant notching the transmission bellhousing to put it there, so that the starter nose didn't interfere with the bellhousing.

The 6R140 bellhousing is much larger in diameter than the ZF6, where the starter mounts, but I think it would still require a bit of a notch in order to accomodate the starter.

The problem with notching the transmission bellhousing is that once you notch it, you pretty much own it. It can never be used as a core in the future and pretty much nobody wants to buy it if you ever want to sell it. Decisions, decisions.

I really want to keep the starter on the driver's side, especially because I'll have twin turbos and their piping and the heat from their piping on the passenger side.

So the low down on the adapter plate is that it isn't a bit deal other than the normal adapter plate detail stuff that needs to attended to. The flex plate is a bigger deal, but no bigger than it would be with any other transmission.

Sorry for being so wordy. I'm out of town working on a project and things are really slow, so I have lots of spare time. Thus I am posting in a rambling manner.

*For those that aren't aware, the ZF6 bellhousing is different for the 6.4, as is the transmission itself.
 

me2

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Before anyone asks, the stock Cummins SAE2 bellhousing adapter will not work, at least not without some modifications and adjustments.

First off, it won't accomodate the alignment dowels on the 6R140. And it also won't match the bolt outside the pattern where the starter mounts.

And then there is the depth issue.

The Cummins SAE #2 bellhousing adapter is about 4 inches thick. The 6R140 setup requires that the flex plate stick out 1 5/16" past the adapter plate. This means the Cummins SAE #2 flexplate (because only it will work with the starter placement in the SAE #2 bellhousing) would need about a 4" spacer between it and the crankshaft.

Another thing about the Cummins SAE2 bellhousing is that it has ears on it for the engine mounts on some applications. I suspect the location of the ear on the passenger side is exactly where the downpipe from my primary (upper) turbo is going to go. The ears don't protrude very far, but they are in that area and I suspect its going to be pretty tight right in that area the way it is.

The other issue with a thick adapter like that is that it increases the length of the engine/transmission assembly from fan to output flange. The Cummins 6.7 is already a bit longer than the Ford 6.4. Anything I can do to keep that assembly as close to stock length as possible makes the fitment of the transmission rear mount and the driveshaft mods easier later on.

One of the reasons I built my own adapter plate for my 5.9 CR swap was that the way I designed things it only had to be 5/16" thick.

That allowed me to run the stock Cummins fan assembly, which provides excellent cooling and keep the ZF6 in nearly its stock location.

This meant I didn't have trouble with the gear shift placement in the stock shifter hole in the cab floor and I was able to use the stock cross member location with a slight reaming of the holes. I did, however, have to shorten the driveshaft, which aside from the hassle is not a big deal.

When I add up all these issues and add in the cost of buying the SAE#2 bellhousing and the Cummins SAE2 flexplate and then machining that adapter and machining the flexplate itself, its not worth it.

I'll talk about the transfer case after I do some testing.

I can't wait to get back home and actually work on something. I've spent the last several months reading and figuring this stuff out. I'm tired of doing that. I'm dying to build stuff.
 
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me2

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More waiting, so therefore more rambling.

Turbos

Why are you building a 600 HP engine for towing ? You'll never need that much power !

I have 325/610 in my old truck right now.

First off, 610 ftlbs isn't enough torque for towing our trailer at 1650 RPM, which is where it runs at 60 MPH in OD with 3.73 gears and 20 inch wheels.

One can argue that is a gearing problem and there is some truth to that. However, I used to run stock 16" wheels on my old truck, which put the engine speed at about 1750 RPM at 60 MPH and it wasn't much better.

Our trailer is 35 feet long, 11 feet high and weighs 14K. And it has a bunch of stuff on the roof. It takes about 75% of full throttle from my 325/610 to pull it in OD at 65 MPH in flat, still conditions. Throw in a 20 MPH headwind and/or a slight grade and the engine is maxed out, stuggling to maintain speed.

It is easy enough to drop a gear into direct, but then the engine is reving 2500 RPM all day where its noisier and uses a lot more fuel. Its not very relaxing. And it still doesn't seem to have a lot of extra power. Even in direct, passing another vehicle on a 2 lane highway is a very slow, dangerous process.

And even when gearing isn't an issue, there are mountain passes that have my old truck down in 2nd gear wound out at 2700 RPM doing 30 MPH.

So I definitely need more power and torque than 325/610. The question then becomes "How much ?"

The next step up in a stock Cummins engine is 350/800 from the new HO Dodge 6.7 engine. I like the 800 ftlbs part, but it doesn't seem like a huge improvement over 610 ftlbs and likewise 350HP over 325HP. It would tow better, but without better gearing, I don't think its enough of an improvement.

So then I started looking at gearing. And the problem is that with most transmissions, when you juggle the rearend and transmission OD gear ratios so that they are good for towing, the engine speed is plain wrong for running emtpy. This is my biggest gripe with all the pickup truck transmissions except the 68RFE and the 6R140, which I think have excellent gear ratios.

So the solution to my towing power issue is twofold.

First, use a transmission with better gearing. By better gearing, I came to the conclusion it needs to be double overdrive with a towing OD gear in the 0.8x range and a cruising OD gear in the 0.6x range. Of all the available transmissions, only the 6R140 and the 68RFE have those ratios. All the others have OD ratios in the low 0.7x range.

I chose the 6R140 because the 68RFE has trouble handling the sort of torque and power I want from my setup.

The second part of the solution is to build a torque/power monster engine so that it pulls well even when the gearing isn't perfect.

Mack used to do this with their highway trucks and still does to some extent. For a while, while everyone else was building trucks with 13 and 18 speed transmissions, Mack was building trucks with torque monster engines and 8 or 10 speed transmissions.

Because I want an off the shelf pickup truck transmission and nothing exotic like a RTOO13, I need an engine that has a wide, torquey powerband like Mack did. I need an engine that pulls good at 1600 and 2600 RPM and everywhere in between. So I have 610 ftlbs right now. Something in the 1000-1200 ftlb range would probably be perfect. Instead of going over that pass at 30 MPH, wound out in 2nd gear, I could now go over at 45 or 50 MPH, at a reasonable engine speed.

So that brings me to the Cummins 6.7, which can certainly be built for monster torque/power.

But it needs more air to do so. That is where twin turbos come in.

And it needs better fueling and engine control. That is where EFI Live comes in.

To be continued.
 
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mines4x4

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I am curious why your wheel size is related to your gear ratios?

20" or 16" wheels don't make any difference if the tires are the same diameter.

I really liked my 6.4 and a couple Spartan tuned 6.4s I drove were monsters. For the cash outlay I would have deleted it, Spartan tuned it, kept some cash in the bank for repairs and bought the wife something pretty instead.

Carry on.
 

me2

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I am curious why your wheel size is related to your gear ratios?

20" or 16" wheels don't make any difference if the tires are the same diameter.
275/65/R20s are 605 revs per mile.
265/75/R16s are 650 revs per mile.
There is about an 8% difference in effective gearing between the two.

I really liked my 6.4 and a couple Spartan tuned 6.4s I drove were monsters. For the cash outlay I would have deleted it, Spartan tuned it, kept some cash in the bank for repairs and bought the wife something pretty instead.
I am not going to get into a debate about whether one should keep a 6.4 or swap it out. Obviously I decided to do the later. Each to his own.
 

amarillo250

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More waiting, so therefore more rambling.

Turbos

Why are you building a 600 HP engine for towing ? You'll never need that much power !

I have 325/610 in my old truck right now.

First off, 610 ftlbs isn't enough torque for towing our trailer at 1650 RPM, which is where it runs at 60 MPH in OD with 3.73 gears and 20 inch wheels.

One can argue that is a gearing problem and there is some truth to that. However, I used to run stock 16" wheels on my old truck, which put the engine speed at about 1750 RPM at 60 MPH and it wasn't much better.

Our trailer is 35 feet long, 11 feet high and weighs 14K. And it has a bunch of stuff on the roof. It takes about 75% of full throttle from my 325/610 to pull it in OD at 65 MPH in flat, still conditions. Throw in a 20 MPH headwind and/or a slight grade and the engine is maxed out, stuggling to maintain speed.

It is easy enough to drop a gear into direct, but then the engine is reving 2500 RPM all day where its noisier and uses a lot more fuel. Its not very relaxing. And it still doesn't seem to have a lot of extra power. Even in direct, passing another vehicle on a 2 lane highway is a very slow, dangerous process.

And even when gearing isn't an issue, there are mountain passes that have my old truck down in 2nd gear wound out at 2700 RPM doing 30 MPH.

So I definitely need more power and torque than 325/610. The question then becomes "How much ?"

The next step up in a stock Cummins engine is 350/800 from the new HO Dodge 6.7 engine. I like the 800 ftlbs part, but it doesn't seem like a huge improvement over 610 ftlbs and likewise 350HP over 325HP. It would tow better, but without better gearing, I don't think its enough of an improvement.

So then I started looking at gearing. And the problem is that with most transmissions, when you juggle the rearend and transmission OD gear ratios so that they are good for towing, the engine speed is plain wrong for running emtpy. This is my biggest gripe with all the pickup truck transmissions except the 68RFE and the 6R140, which I think have excellent gear ratios.

So the solution to my towing power issue is twofold.

First, use a transmission with better gearing. By better gearing, I came to the conclusion it needs to be double overdrive with a towing OD gear in the 0.8x range and a cruising OD gear in the 0.6x range. Of all the available transmissions, only the 6R140 and the 68RFE have those ratios. All the others have OD ratios in the low 0.7x range.

I chose the 6R140 because the 68RFE has trouble handling the sort of torque and power I want from my setup.

The second part of the solution is to build a torque/power monster engine so that it pulls well even when the gearing isn't perfect.

Mack used to do this with their highway trucks and still does to some extent. For a while, while everyone else was building trucks with 13 and 18 speed transmissions, Mack was building trucks with torque monster engines and 8 or 10 speed transmissions.

Because I want an off the shelf pickup truck transmission and nothing exotic like a RTOO13, I need an engine that has a wide, torquey powerband like Mack did. I need an engine that pulls good at 1600 and 2600 RPM and everywhere in between. So I have 610 ftlbs right now. Something in the 1000-1200 ftlb range would probably be perfect. Instead of going over that pass at 30 MPH, wound out in 2nd gear, I could now go over at 45 or 50 MPH, at a reasonable engine speed.

So that brings me to the Cummins 6.7, which can certainly be built for monster torque/power.

But it needs more air to do so. That is where twin turbos come in.

And it needs better fueling and engine control. That is where EFI Live comes in.

To be continued.

This is so cool to read and shows me that you realy know what towing is about. I am in the same boat with my 35 ft. Titanium 5er.
 

Spectre32

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Looks pretty cool man, keep the updates comming. Pictures are always a good/welcomed addition as well!
 

Dzlnut

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Very interested in this thread, you obviously have the brains to get this project done. Awesome!!!
 
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