I have one issue with a local GM dealer that REALLY soured me on the obscene prices they charge for work. When our 2004 Lesabre was new, my wife would take it to the selling dealership for oil changes....after the first four or five times, I filed away the invoices and upon looking at them I realized the dealership was charging her for 5 quarts of oil, even though the 3.8 V6 had a recommended oil and filter change capacity of 4.5 quarts. They were billing her for TEN UNITS per change, a unit being a half quart. I took the invoices and went to the dealership and inquired: "Can you tell me if you are overcharging for a half quart of oil not put in the engine, or are you overfilling it by a half quart?" THEY WOULD NOT GIVE ME A STRAIGHT ANSWER. The service manager left and came back with a check in the amount of the 4 or 5 excess half quarts of oil, and apologized and also gave me a coupon good for a free oil and filter change....I gave the coupon to someone else because I had NO intention of ever returning there...any dealership that is scamming customers in little ways like that will most certainly scam them in other ways. I wonder sometimes just how many "half-quarts" they scammed customers out of over the years.