Noises During Shifting problems of the 2007 Chevrolet Silverado

The contact owns a 2007 Chevrolet Silverado. The contact heard a noise coming from the automatic transmission and the vehicle was hesitant to shift into gear. The dealer repaired the vehicle under warranty. The failure recurred and the vehicle was taken back to the dealer. They stated that there was an issue with the vehicle and notified the manufacturer. The manufacturer advised the dealer not to make any further repairs until the transmission actually failed. The dealer obeyed the manufacturer. The VIN was unknown. The failure and current mileages were less than 20,000.

The contact owns a 2007 Chevrolet Silverado c1500. When attempting to accelerate the vehicle at 10 mph, the contact heard a loud clunking and revving noise as if it were downshifting or upshifting. The dealer speculated that the transmission was the cause of the failure. The technician referenced TSB number 10022769, but there was no current remedy. The contact is in the process of notifying the manufacturer. The failure mileage was 37,000 and current mileage was 41,000.

Vehicle is parked in garage overnight,get in to start ,shift lever in park,turn on key,vehicle's transmission sends out a "clunk", as if to engage and go forward or backward. This type of action started around 8000 miles as a slight, "clunk" extending into 49000 miles with a hard jarring"clunk". Of course I took it to dealer in the course of the warranty ,had them note and record defect,however dealer could not get vehicle to perform this operation while in their possession which extended over night and sometimes 2 nights. While the vehicle does not do this on a regular basis,it is notably getting a harder sounding, more pronounced "clunk". The shifting noise of the transmission is becoming evident, that is in low speed there is more rough clunking as the transmission goes through it's gears.