Hey all,
New to the forum, but I need some advice so I'll give it a shot.
Winter of '21 my transfer case chain started slipping. I snow plow with the truck during the winter, so I didn't mess around trying to open up the tcase. I dropped in a kodiak truck reman 261XHD and had to install their slip yolk to validate the warranty. I didn't get one of the snap rings in the u-joint seated properly and threw a cap as soon as I got on the highway which vibrated the transmission to death. Sheared the rear housing clean off. Painful mistake, I know.
Anyways, I went with a local transmission shop, Jim & Sons Transmission, here in Canton, Ohio for a full service and new rear housing. I figured while I'm here, might as well build it. I would've liked to order one already assembled, but I needed the truck to go to work and didn't have the time to install the trans myself. I explained it is a work truck (plowing, hauling equipment, etc.) and I'm planning on some modifications in the future (tune and turbo). I was assured they would build be a transmission that would handle it. They installed alto c1-c5 clutches, a transgo shift kit, and an 'in-house' billet single disk converter.
Trans worked great until I installed efi tunes from DuramaxTuner, namely levels 4 and 5. Extremely harsh shifts, clunks out of park/reverse, and when it went into limp mode on a 2-3 shift, I took it right back. They cleared the codes and said everything was fine. That's when I realized I screwed up, I knew everything was NOT fine. Naturally, a few weeks later it went into limp mode again. This time on the highway on a 5-4 downshift. They finally agreed to open it up again to find burnt c2 and c3 clutches. They replaced them and were sure that the trans tune was at fault. They said it wouldn't be as aggressive, but a stock transmission tune would solve the problem. Again, I wasn't sold, but I had to play their game. The stock trans tune didn't solve anything (obviously) and their response was "it's just too much power from the engine tune." Stock turbo, stock fuel system, and a hot tune is "too much power" for their transmission...
At this point, I was at the end of my rope. I knew these people were unable to help me any longer. They finally settled and refunded the price of the aftermarket parts.
So this is where I'm at: A couple thousand deep in this "built" transmission, duramaxtuner efi tunes, clunky selector shifts, harsh shifts under power, and limp mode on 5-4 downshifts under power, every time. Trans does fine if I'm going easy on it. I've also experienced reduced power, almost felt like the truck was being governed. Under full throttle it just hovered between 1500-1600 rpm. It was freezing when that happened, 15-20 below zero, so it could be unrelated, idk.
I'm ready to buy a built tans out the box to install myself, but it seems like there so many options. Suncoast, SDP, ATS, BD, Wehrli Custom, DMAX Store, DDP, Merchant, Xcalliber... I like the idea of a DuramaxTuner transmisson to match the tunes, but they haven't been very helpful to me throughout this process, either. I'm also not opposed to looking elsewhere for tunes, if need be.
I'm not looking to build a 1000+ hp drag truck or anything crazy. A bigger turbo and fuel to support will be the furthest I take this build. I'm looking for a truck that's reliable to do work, and fun to drive.
Everyone I've talked to personally has something different to say, none of which have performance built duramax trucks. So, I figured this is the place to get some real advice from real duramax guys.
Any insight/suggestions would be greatly appreciated!
New to the forum, but I need some advice so I'll give it a shot.
Winter of '21 my transfer case chain started slipping. I snow plow with the truck during the winter, so I didn't mess around trying to open up the tcase. I dropped in a kodiak truck reman 261XHD and had to install their slip yolk to validate the warranty. I didn't get one of the snap rings in the u-joint seated properly and threw a cap as soon as I got on the highway which vibrated the transmission to death. Sheared the rear housing clean off. Painful mistake, I know.
Anyways, I went with a local transmission shop, Jim & Sons Transmission, here in Canton, Ohio for a full service and new rear housing. I figured while I'm here, might as well build it. I would've liked to order one already assembled, but I needed the truck to go to work and didn't have the time to install the trans myself. I explained it is a work truck (plowing, hauling equipment, etc.) and I'm planning on some modifications in the future (tune and turbo). I was assured they would build be a transmission that would handle it. They installed alto c1-c5 clutches, a transgo shift kit, and an 'in-house' billet single disk converter.
Trans worked great until I installed efi tunes from DuramaxTuner, namely levels 4 and 5. Extremely harsh shifts, clunks out of park/reverse, and when it went into limp mode on a 2-3 shift, I took it right back. They cleared the codes and said everything was fine. That's when I realized I screwed up, I knew everything was NOT fine. Naturally, a few weeks later it went into limp mode again. This time on the highway on a 5-4 downshift. They finally agreed to open it up again to find burnt c2 and c3 clutches. They replaced them and were sure that the trans tune was at fault. They said it wouldn't be as aggressive, but a stock transmission tune would solve the problem. Again, I wasn't sold, but I had to play their game. The stock trans tune didn't solve anything (obviously) and their response was "it's just too much power from the engine tune." Stock turbo, stock fuel system, and a hot tune is "too much power" for their transmission...
At this point, I was at the end of my rope. I knew these people were unable to help me any longer. They finally settled and refunded the price of the aftermarket parts.
So this is where I'm at: A couple thousand deep in this "built" transmission, duramaxtuner efi tunes, clunky selector shifts, harsh shifts under power, and limp mode on 5-4 downshifts under power, every time. Trans does fine if I'm going easy on it. I've also experienced reduced power, almost felt like the truck was being governed. Under full throttle it just hovered between 1500-1600 rpm. It was freezing when that happened, 15-20 below zero, so it could be unrelated, idk.
I'm ready to buy a built tans out the box to install myself, but it seems like there so many options. Suncoast, SDP, ATS, BD, Wehrli Custom, DMAX Store, DDP, Merchant, Xcalliber... I like the idea of a DuramaxTuner transmisson to match the tunes, but they haven't been very helpful to me throughout this process, either. I'm also not opposed to looking elsewhere for tunes, if need be.
I'm not looking to build a 1000+ hp drag truck or anything crazy. A bigger turbo and fuel to support will be the furthest I take this build. I'm looking for a truck that's reliable to do work, and fun to drive.
Everyone I've talked to personally has something different to say, none of which have performance built duramax trucks. So, I figured this is the place to get some real advice from real duramax guys.
Any insight/suggestions would be greatly appreciated!
