• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

I've decided to do a Cummin's conversion

F

FellowTraveler

Well-Known Member
Messages
4,757
Reaction score
6,151
Location
Nature Coast
I have a 94 Cummin's 12 valve w/60k I'm going to install in the 99 Burb.

Wondering if I can get any input from those who have done this.
I'll be using the 4L80e and because I still have the AutoTrac thinking the stock ECM will do for trans control, etc., I do plan to go w/NP241c in the near future.

Right now doing research and getting prices of all the conversion components then after careful evaluation pulling the trigger so to say.

I'll be posting up an enhanced 6.5td complete w/all accessories that has 125k miles, no blow-by runs great.
 
FellowTraveler said:
I have a 94 Cummin's 12 valve w/60k I'm going to install in the 99 Burb.

Wondering if I can get any input from those who have done this.
I'll be using the 4L80e and because I still have the AutoTrac thinking the stock ECM will do for trans control, etc., I do plan to go w/NP241c in the near future.

Right now doing research and getting prices of all the conversion components then after careful evaluation pulling the trigger so to say.

I'll be posting up an enhanced 6.5td complete w/all accessories that has 125k miles, no blow-by runs great.
Click to expand...
I'm surprised you're going this route, but I look forward to seeing the results.
 
I did a Cummins 12 valve in a 96 dually 4x4 cclb . It was a beast for sure. There is so much aftermarket support for the swap now that I did not have.
I do have a bread truck engine to trans adapter complete with starter crank hub adapter, bolts, flex plate......ect I sell for $750 + shipping.
As far as trans controller I've been there done that. To make a TCM work is not worth the effort. IMO get a stand alone controller like the QuickShift 1 or 4 I offer. Ask Nate about it, he just got one.
 
I talked myself out of one REAL QUICK! I got stuck between a 12 valve and a 24 valve when I 1st decided to do an engine swap because the 6.5 needed more than I wanted to do, that ended that thought instantly. If you want the engine and trans straight, then the DESTROKED kit is about your only option(keep in mind that setup requires there block adapter, there flexplate, and a 6.0L powerstroke starter). If you don't mind the 7 degree offset, then the bread truck adapter will do the job. As to the trans controller, an aftermarket programmable is the only way to go. The OEM controller will be a nightmare behind a CUMMINS as the shift points and lockup schedules will not match the CUMMINS torque curve. Go aftermarket there. For the transfer case, not sure how integrated it is into the vehicle, or if it works stand-alone. If it's integrated into the class 2 data bus, and reads data signals from the ECM, then chances are it will not work with your swap even if you keep the factory 6.5 ECM. The speedo will work so long as you stick with a GM transfer case, and keep the VSSB, and the ABS should also function so long as the VSSB is retained. If you want a NP241, I have one sitting in my shed collecting dust. only thing it would need is the shift arm as I had to swap the old one to the NP261XHDC I put into mine.

For the actual swap, as you probably already have read, it is TIGHT! Engine mounts will require some finagling to make work, and it will be a juggling act to get the CUMMINS back tight to the firewall, and maintain radiator clearance. I believe those who have done them, have had to swap to an early style fan drive and fan clutch as the 94-02 drive sticks out to far. For an intercooler, you will be stuck with a DODGE unit as the DURAMAX one requires moving the cooling stack brearward, and the long CUMMINS won't allow for that. I believe you can use the 03-05 power steering brackets to ru na belt driven pump as I believe clearance for the gear driven will be tight with the vacuum pump keeping it moved so far rearward. And the compressor and alternator will be your other hurdle.
 
Understand about the aftermarket stand alone trans controller, it will be w/454 throttle cable/pedal & GM stand alone cruise control & cable.

As for the t-case I'll PM you (I want it), the autotrac controller is tied into the ABS somehow (I don't remember right now) so I have to get past that and use only one of it's 3 speed sensors on the 241 case.

I see one individual used a GM hydroboost can on the dodge p/s pump.

For the cooling stack I'm mulling around extending the grill out towards the front some.

AC/ALT brackets will be an issue as most require body lift or cowl induction hood to clear the compressor....I don't like either option so the jury is out on this right now.

As always, thanks FERM........
 
DMT said:
Fellow, why are you going this route? I thought you were one of the maestros of the GM diesel, a sorcerer of the six five. What are the main drivers of your decision?
Click to expand...
Well, I have a 94 Ram 3500 rotting around a 60k Cummin's motor, the boss lady saw a c2500 converted to the cummins and liked it and suggested I do it, honestly I'm having second thoughts especially since n8in8or posted his latest video. I'm actually leaning towards what FERM said about it....
 
IMO any conversion you do needs to be your dream truck with your dream engine. I've done too many to ever think one will be fast and easy. You can't do it trying to save money or it will bite you.
If your not planning on owning it for a decade afterwards, it's a mistake.

If it's for the wife, make sure she has driven something similar to know what it will be when done.

On a Dodges everybody beats up the problems, but that is a serious vibrating, heavy engine. The steering problem in Dodge that doesn't exist in GM- it will when you add that weight and vibration. The dodge dash is a given nightmare design flaw, but most of the other problems are effected by the cummins. Look up problems in diesels vs gas. The same thing holds true in the p30 trucks- all too familiar with those.

I'm not going to say it's a mistake to replace a 6.5 with any cummins, just be 100% that is what you want.
 
Taking on this project is not for everyone, as it will likely involve more than a few surprises. But you have shown not to be shy about taking on big projects with your Burb, so it may be a nice, beefy project to sink your teeth into. You have already upgraded your front suspension with stronger torsion bars, if I remember right. That should help with the extra weight of the Cummins. If you decide to go forward with it, I will certainly follow the project with great interest. I might even be interested in the Navistar that you are swapping out. Maybe we could have a private conversation about that. Good luck.
 
I would have found an identical burb with a 454 and cummins swapped it, then when you realized that the cummins is not a nice smooth running refined engine worthy of a passenger vehicle, sell it to someone who thinks its the coolest thing ever. :)

Then, you will still have a 6.5L burb that never got modded.

DO tell, what is the issues with the DS4? I have had enough negative DB2 fun here that I will never DB2 swap a DS4 truck.
 
DMT said:
Taking on this project is not for everyone, as it will likely involve more than a few surprises. But you have shown not to be shy about taking on big projects with your Burb, so it may be a nice, beefy project to sink your teeth into. You have already upgraded your front suspension with stronger torsion bars, if I remember right. That should help with the extra weight of the Cummins. If you decide to go forward with it, I will certainly follow the project with great interest. I might even be interested in the Navistar that you are swapping out. Maybe we could have a private conversation about that. Good luck.
Click to expand...
No upgrade to t-bars all 8.6k+ GVWR Burbs have the next to the highest rate t-bars GM used....the regular 8.6k has a t-bar rating below this...
 
Put a baby Duramax with its transmission out of a K1500 in it! You would have a 28+ MPG Suburban with roughly the same power and torque in stock form as a stock 6.5, but much easier, cheaper and reliable to increase performance of it than the 6.5.
 
Last edited:
Husker6.5 said:
Put a baby Duramax with its transmission out of a K1500 in it! You would have a 28+ MPG Suburban with roughly the same power and torque in stock form as a stock 6.5, but much easier, cheaper and reliable to increase performance of it than the 6.5.
Click to expand...
Are you talking about the new 4 cylinder? If so it will be awhile before they come down in price enough to afford a swap with one.
 
You must log in or register to reply here.
Back
Top