15435A - SERVICE UPDATE (REVISED SERVICE PROCEDURE). THIS BULLETIN PROVIDES A SERVICE PROCEDURE TO REPLACE THE TORQUE CONVERTER ON CERTAIN 2015 MODEL YEAR CHEVROLET SILVERADO HD, GMC SIERRA HD AND GMC SIERRA DENALI HD VEHICLES EQUIPPED WITH AN ALLISON 6-SPEED AUTOMATIC TRANSMISSION (RPO MW7). THESE VEHICLES MAY HAVE BEEN ASSEMBLED WITH AN INCORRECTLY MACHINED TORQUE CONVERTER. CUSTOMERS MAY EXPERIENCE NOISE, POOR PERFORMANCE AND, IF THIS CONDITION IS NOT CORRECTED, EVENTUAL TRANSMISSION FAILURE.
