NHTSA Complaint #11550011 — 2018 CHEVROLET SUBURBAN

9/29/22 (123k miles) TECHNICIAN: - Test drove vehicle, inspected transmission operation & found gear train noise / L3, in approximately 1st through 3rd gears. Tach was jumping up to about 200 rpms when converter locked up and then would go back down. Monitored on scanner and found converter slipping in and out of lock up. - Scanned computer control modules & found no codes. - Inspected transmission fluid level & condition, found transmission fluid was full and red, note; customer noted fluid was changed recently and was dark and burnt with metal shavings in it during the change. (photo of metal shavings). - Inspected exterior of transmission for leaks & damage, found no leaks or damage. - Determined there is a lack of lockup pressure or hydraulic pressure and internal damage to the transmission assembly. - Recommends replacing the transmission assembly with a unit with an improved torque converter. (We replace).