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Hemi to 12 valve Cummins swap

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Hemi to 12 valve Cummins swap

  #1  
Old 09-13-2008, 04:02 PM
YJoe
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Default Hemi to 12 valve Cummins swap

I have an 04 2500 4x4 Quadcab. It has an Auto and a 5.7L. It has 68,000 miles on it and I have had tons of nickel and dime crap go wrong with this motor. Truck is awesome, motor sucks! Most recently (this week) its in the shop for broken exhaust manifold bolts. Luckily it's still under power train warranty otherwise it would have been a $1600 fix!!! They had to pull both heads to get out the snapped off bolts.

So I'd love to ditch this crap Hemi. I was thinking a 24 valve Cummins out of a similar year truck but it still all electronic and a lot more $$$$ to build. So I think ideal would be dropping in a 12 valve 6BT. I could easily get a good 3-400 HP out of one which is what I'm shooting for. Simple, reliable, efficiant, and tows my Jeep with ease. Wondering if anyone here has ever done such a swap. I'm wondering if it's even doable and still keeping it 50 state emissions legal. I'm pretty sure the last year for the 12 valve was 1997... but I could be wrong Not sure if this is like gasses emissions where you need to keep the drivetrain newer then the truck.

I'd also like to convert it to a manual trans. Anyone know if the 12 valve and 24 valve Dodge Cummins share the same trans bolt pattern? What trans options are out there for this motor? (12 valve)

Yeah loaded question. Any little tidbits would be appreciated. I'm quite experienced at drive train swaps but I've never dealt with anything this new or with much diesel or Dodge stuff.

Joe
 
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Old 09-13-2008, 04:09 PM
Splashman
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Ha, this is actually my post..... just figured out my password
 
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Old 09-13-2008, 04:34 PM
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It's funny, well evidently not for you, since you are the one having problems with your engine, but EVERY post I've ever read like this is just the opposite. They all talk about the engine being super reliable but the rest of the truck falling apart around it. Ball joints, tie rods, death wobble issues, transmission nightmares, dash cracking, etc.
 
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Old 09-13-2008, 04:36 PM
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I'd take it and trade it for a diesel that you want instead of trying to figure all of that out. My 2 cents
 
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Old 09-13-2008, 04:43 PM
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yea you might as well just go and buy a new truck or a used one that has what you want. itd be alot less headaches.
 
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Old 09-13-2008, 04:58 PM
John M
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The trucks are too smart to let you do the swap. Seriously, there's too much electronic action happening in the background to ever let you swap powertrains.

Take the instrument cluster for example. It doesn't have a signal for the speed, temp, fuel, oil pressure, etc. It reads it all off the bus and displays it accordingly. The display "knows" whether you've got 4WD, an auto or manual, and dozens of other things. They warn you not to swap clusters either unless it's a replacement unit from the dealership.

Did you know your the unit inside the speedo cluster has a special "crash" mode? If it detects airbag deployment, it disables the door lock control, unlocks all doors, and turns on the interior lights.

Now take this complexity and spread it among the engine computer and other controllers in the truck and you'll see why it's far to expensive and difficult to do a swap when you could trade in towards the vehicle you want.

As for me, my Hemi is perfect as it's about to reach the 60k mark and I'd never switch for another truck - except maybe an 09 Ram!
 
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Old 09-13-2008, 07:26 PM
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Yup, the computer control would be just about impossible to do.

What is the difference in weight between the drivetrains? You may also need a whole new suspension that nobody makes.
 
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Old 09-13-2008, 11:21 PM
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Save yourself a lot of wear and tear. Sell your truck and go shopping.

Rick
 
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Old 09-14-2008, 08:26 AM
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Originally Posted by kenihemi View Post
Yup, the computer control would be just about impossible to do.

What is the difference in weight between the drivetrains? You may also need a whole new suspension that nobody makes.
The make them, factory CTD springs. This is a 2500, solid AAM 9.5 front axle. Not a IFS 1500.
 
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Old 09-14-2008, 08:37 AM
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Originally Posted by John M View Post
The trucks are too smart to let you do the swap. Seriously, there's too much electronic action happening in the background to ever let you swap powertrains.

Take the instrument cluster for example. It doesn't have a signal for the speed, temp, fuel, oil pressure, etc. It reads it all off the bus and displays it accordingly. The display "knows" whether you've got 4WD, an auto or manual, and dozens of other things. They warn you not to swap clusters either unless it's a replacement unit from the dealership.

Did you know your the unit inside the speedo cluster has a special "crash" mode? If it detects airbag deployment, it disables the door lock control, unlocks all doors, and turns on the interior lights.

Now take this complexity and spread it among the engine computer and other controllers in the truck and you'll see why it's far to expensive and difficult to do a swap when you could trade in towards the vehicle you want.

As for me, my Hemi is perfect as it's about to reach the 60k mark and I'd never switch for another truck - except maybe an 09 Ram!
OK I'm still thinking the dash / other control systems are regulated differently then the engine... as they usually are. Pretty sure you can pull the engine and the trans out and still have everything else function. I realize the Oil psi, temp, tach and voltage won't work with the new motor, but there are ways around that. Saying that it's way to complex just doesn't cut it. It's just a matter of getting good service manual with detailed wiring schematics and figuring out what needs what. Never said it would be easy. The motor will run by its self... just gota make the truck not give a CEL.

As for buying a new truck, well I figure my Hemi in a year or 2 will be worth $9-10K tops? A new CTD is $35-40.... used is $25-$30. I'm pretty sure an entire 6BT / trans / case rebuild and swap won't cost $20K. Even with figuring out the electronics.

Not really looking for reasons why to not do it, looking for people with experience on doing it.
 

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