Time to find a new mechanic. Change your oil every 3k to 5k replace air filter every 8k to 12k and dont buy cheep gas!!!!! These things will run for ever
Even then you are wasting your money. Unless you live down a dusty road or drive cold short trips the oil should last about 6-10k and the air filter is recommended to be changed at 50k on most GM vehicles. Since it is dusty in Utah I change air filters about 35k.
Fuel services are a big mark up item. Most just put a bottle of techron into your tank. Unless you always use crappy gas your fuel system should be good to go with a bottle of techron once in a while. That is not required by GM though.
I agree on the tranny fluid. GM has a severe and a regular service intervals. It isn't hard to fall into the severe category (drive in hot temps, cold temps, stop and go traffic, hills, etc). I change mine out every 45-50k.
Do you have 4WD or AWD? If so the transfer case requires to be changed at 50k. GM doesn't have a requirement for the axles but I change mine about every 40k anyway.
GM does recommend using a Top Tier fuel. I personally think it is part gimmick since some big names are not on the list. But I do use Chevron when it is available.
Change the air filter if you haven't already.
