6.7 Cummins manual transmission

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Cowcatcher

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I can see the B&M unit is physically larger, and looks beefier. Looks to be machined cylindrical steel housing instead of a cast aluminum housing as is the factory unit.

I can't see where the factory unit failed? Am I missing an obvious crack? Or did it just drop parts down into the trans?

It looks like in post #1 the second picture the shell of the box just failed causing the parts inside to lose tolerances eventually spreading and come apart. Is that the diagnosis?
Yes if you look at the pics in the first post, look at the pictures of the bottom of the shifter. You can see when looking at the opposite sides that parts are missing from one side. The parts were found in the bottom of the trans and it appears they took out some gears on their journey. Several of the parts are just held with a little tack weld. One builder I talked to said he welds them better on any trans he builds where the customer wants to retain the factory shifter.
 
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Cowcatcher

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I wish dodge had either kept the NV5600 or copied the ZF6. The G56 was not a good move. How many clutches have you put in that truck? Every time I see a 4th gen G56 for sale, it’s had a clutch done within the first 25k miles and usually another before 100k.
Truck has its 3rd clutch in it right now with maybe 10k miles on it. Exact mileage is noted somewhere. The original clutch didn’t last long. I deleted and tuned the truck when the truck had 10-15k miles on it. Shortly following that hp and torque gain the clutch would no longer hold 4th gear. I put a Valair dual disk in at that time. Somewhere around 120k miles I put another valair dual disk in. I considered swapping to a south bend that time but would’ve had to by their hydraulics also so I went valair again since I already had valairs hydraulics. Next time I might go ahead and try a south bend. I bought the truck new in 2010 and I intend to own it forever. Sometimes I question that because the truck hasn’t depreciated that much but the cost difference to replace it would be ridiculous, I don’t want/need the latest interior design and I can run with any new one loaded. Some of the above mileage numbers may be off just a tick cuz I do know it just rolled past 140k.
 

Mr.Glock

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Hindsight is always 20 20. But at the time did you walk away with a pile of cash smiling?

Back to the OP, you would think the B and M to be very well-manufactured unit and take care of the problem.

It was one I couldn’t turn down. He was a rich kid and he and daddy split it. The kid was 20 years old. I was in HotSprings Ark, with my Jeep in tow behind it on a dual axle trailer. We were up in the mountains in a trail and another set of Jeeps was coming down. They were asking if one us had the 98 Dodge 12V. He came to camp that night with his Dad and they did not bull **** around. If I was as wealthy back then as I am now, no way. But when you’re building a life and get a stupid offer, you had to take it.
 

Cowcatcher

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It was one I couldn’t turn down. He was a rich kid and he and daddy split it. The kid was 20 years old. I was in HotSprings Ark, with my Jeep in tow behind it on a dual axle trailer. We were up in the mountains in a trail and another set of Jeeps was coming down. They were asking if one us had the 98 Dodge 12V. He came to camp that night with his Dad and they did not bull **** around. If I was as wealthy back then as I am now, no way. But when you’re building a life and get a stupid offer, you had to take it.
I’ve let a few vehicles go in the last 20 years that I ended regretting I sold. I just sold one last weekend to offset this transmission for this truck. It was a 98 suburban 4x4 leather and all. I bought it from the original owner and it rode awesome down the road. I actually preferred riding in it over my wife’s Escalade but I kinda had 3 personal vehicles and my main one being the dodge truck needed work. As far as using it I won’t miss the suburban I reckon but I liked admiring how good of shape it was in for 25 years old.
6CFEBA4D-3F44-43D9-8B42-41C6C0055F80.jpeg
 

Dumpstick

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One of the best ideas Dodge ever had was to stick the Cummins in a pickup.

One of the worst ideas Dodge ever had was to try using in-house transmissions behind said Cummins. It took Dodge decades to get a suitable transmission in the diesel pickup.

I've got a 2005 with an auto. I have put some fairly serious money in the 48re, but I'm not foolish enough to pretend it's a heavy hauler. A travel trailer is the normal load.
but...
I have used it to pull my Class 8 dump truck out of a hole, and once pulled a broken-down loaded box truck out of an intersection.
 

Roy14

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One of the best ideas Dodge ever had was to stick the Cummins in a pickup.

One of the worst ideas Dodge ever had was to try using in-house transmissions behind said Cummins. It took Dodge decades to get a suitable transmission in the diesel pickup.

I've got a 2005 with an auto. I have put some fairly serious money in the 48re, but I'm not foolish enough to pretend it's a heavy hauler. A travel trailer is the normal load.
but...
I have used it to pull my Class 8 dump truck out of a hole, and once pulled a broken-down loaded box truck out of an intersection.
What’s strange is if you fix all the issues behind the 47/48 autos, they’re some of the most preferred units for guys building big numbers in pulling trucks.
 

trekrok

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Can you even get a manual behind a diesel truck nowadays? With the amount of torque generated by these things I can see manual gears and clutches being a problem.
 

Cowcatcher

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Can you even get a manual behind a diesel truck nowadays? With the amount of torque generated by these things I can see manual gears and clutches being a problem.
I’m pretty sure that Dodge was the last one to offer a manual behind a diesel and that was 2018 or 19.
 

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