Robert Summers sent a message to Mary Barra that said:
I purchased a new 2019 Chevrolet Colorado in January 2020 from Boniface Hiers Chevrolet Dealership in Melbourne Florida. After the truck is warmed up there is a loud humming noise when the Air Conditioner is turned on & when accelerating and slowing down there is a loud tinny sound also. I have had it in the shop 7 times to correct the problem. They replaced the compressor twice and the last time removed and inspected the expansion valve. They say it is normal and other like trucks have the same noise. Cause is due to an engineering change. There are write ups on the internet addressing this problem with possible repairs. I made copies and gave them to the Service Director. Apparently none of the problems pertained to my truck.
I am sorry to have to bother you with this problem, but I do not believe I should have to deal with something that is a result of a design flaw. Surely someone at GM has a fix for this. I cant believe GM wants vehicles with problems on the road. Does not do well for your reputation. I am and have been a GM fan as for all of my family. Please, can you help resolve this problem?