Chevyexpress3500

I bought a new 2019 Chevy Express 3500 with a 6.0 L Vortec motor and with the 6 speed automatic transmission. I experienced the chuggles or the transmission studder but didn't know what it was until I did some research and saw these forums. I took it to the dealer and they told me it was the transmission learning how I drive and it will slow down when under load to protect the motor. I couldn't accept that and had to test drive it with the service rep, the technician, the lead technician, the lead service rep, and then with a special GM tech engineer. They all agreed there is a problem. First they replaced the ECU and that did not fix anything. Then they replaced the torque converter and flushed the ATF and that fixed the problem. Hope this helps someone dealing with the same issue! I was dreading bringing it to the dealer because there was no service engine light with a code for them to work with. Reading everyone's struggles also made it seem like it would be a long painful process to work with the dealers service department. Flush your ATF first and if that doesn't fix it then replace your torque converter!!

I bought a new 2019 Chevy Express 3500 with a 6.0 L Vortec motor and with the 6 speed automatic transmission. I experienced the chuggles or the transmission studder but didn't know what it was until I did some research and saw these forums. I took it to the dealer and they told me it was the transmission learning how I drive and it will slow down when under load to protect the motor. I couldn't accept that and had to test drive it with the service rep, the technician, the lead technician, the lead service rep, and then with a special GM tech engineer. They all agreed there is a problem. First they replaced the ECU and that did not fix anything. Then they replaced the torque converter and flushed the ATF and that fixed the problem. Hope this helps someone dealing with the same issue! I was dreading bringing it to the dealer because there was no service engine light with a code for them to work with. Reading everyone's struggles also made it seem like it would be a long painful process to work with the dealers service department. Flush your ATF first and if that doesn't fix it then replace your torque converter!!