According to TSB (Technical Service Bulletin) 18-NA-355, the latest update addresses “torque converter clutch (TCC) shudder conditions on 8L45 and 8L90” eight-speed automatic transmissions, RPO codes M5N, M5T, M5U, and M5X. Affected vehicles include Chevrolet, GMC and Cadillac vehicles.
https://static.nhtsa.gov/odi/tsbs/2019/MC-10163890-9999.pdf
Lenny
2016 GMC Yukon Denali 58000 miles.
