Hi everyone. I’ll get to the point. 2015 Silverado 2500HD CCSB LT 6.0. Bought it from my 72 year old neighbor(1st/original owner) a year and a half ago with 37,400 miles. At 40,000 miles the torque converter started failing. Trailered it to a shop who pulled trans, did a hot flush, replaced torque converter with a reman unit with a billet piston, Sonnax zip kit, welded 345R drums(I think without looking) and tuned trans. They did their stage 1 upgrade on my transmission. It didn’t need rebuilt, but I figured since it was out of the truck, to go ahead and rebuild it. They filled it with Dex3, which I questioned, but they said it was fine and that Dex6 was smoke and mirrors.
Ever since, at low speed(35-40mph/low RPMs(1200-1500RPMs), it feels like there’s a miss or shudder. If I’m cruising along at whatever speed and let off of the gas and coast and then slightly give it throttle, it will do it for a second or two.
I’ve had it to two different shops to run diagnostics only on it plus I’ve hooked it up to a Snap On Solus Legend scan tool and no codes. If I put it in tow haul mode, it generally doesn’t allow the engine to drop down RPMs low enough to cause it. I can get replicate it. Also, when I first drive the truck for the day, there is a 100-250RPM flare on the 2-3 shift. After it does it, it doesn’t do it again the rest of the day. It doesn’t matter if I let the truck warm up for 30 seconds or 10 minutes, it does it regardless of outside temps.
Another issue….when I leave and go somewhere, the truck seems peppy and runs good. Acceleration and power seems good. After it warms up, sometimes it acts as if I’m holding the brake or something because acceleration is slow and I have to give it more throttle to get going or to pick up speed. There’s definitely something wrong because it’s intermittent and driving me crazy. When it runs normal, I love it. When it acts like it has no power, I hate it and want to sell it. I’ve checked air filter, brakes and calipers, looked at the converters looking for an orange glow in the dark, spun the fan clutch to make sure it’s not locked up, and looked under the hood in the dark while truck is running looking for sparks from a bad wire or coil. And like mentioned, it’s been scanned 3 different times and no codes and no check engine light. There were at least 3 times the Service Antilock/Stabilitrak message came up and went away immediately. It never stored a code.
It currently has just over 43,000 miles on it. Please help because I like the truck and want to get it figured out. Prices and interest rates are too high on new ones.
Ever since, at low speed(35-40mph/low RPMs(1200-1500RPMs), it feels like there’s a miss or shudder. If I’m cruising along at whatever speed and let off of the gas and coast and then slightly give it throttle, it will do it for a second or two.
I’ve had it to two different shops to run diagnostics only on it plus I’ve hooked it up to a Snap On Solus Legend scan tool and no codes. If I put it in tow haul mode, it generally doesn’t allow the engine to drop down RPMs low enough to cause it. I can get replicate it. Also, when I first drive the truck for the day, there is a 100-250RPM flare on the 2-3 shift. After it does it, it doesn’t do it again the rest of the day. It doesn’t matter if I let the truck warm up for 30 seconds or 10 minutes, it does it regardless of outside temps.
Another issue….when I leave and go somewhere, the truck seems peppy and runs good. Acceleration and power seems good. After it warms up, sometimes it acts as if I’m holding the brake or something because acceleration is slow and I have to give it more throttle to get going or to pick up speed. There’s definitely something wrong because it’s intermittent and driving me crazy. When it runs normal, I love it. When it acts like it has no power, I hate it and want to sell it. I’ve checked air filter, brakes and calipers, looked at the converters looking for an orange glow in the dark, spun the fan clutch to make sure it’s not locked up, and looked under the hood in the dark while truck is running looking for sparks from a bad wire or coil. And like mentioned, it’s been scanned 3 different times and no codes and no check engine light. There were at least 3 times the Service Antilock/Stabilitrak message came up and went away immediately. It never stored a code.
It currently has just over 43,000 miles on it. Please help because I like the truck and want to get it figured out. Prices and interest rates are too high on new ones.
