The brother in law runs a GM engine lab. He has opinions on their engine tolerances. His track car is some 500 hp Nissan something or other. He doesn't recommend GMs, generally.
I worked at a large chain oil change place for about 7 months, 70-100 cars a day through our store. All this filter priming talk is funny. Only 2 kinds of vehicles EVER had their filters primed; big diesels, and certain small ford cars. Nothing else, canister nor cartridge, was ever primed.
On 20 weight oils, we noticed that the ONLY make which wasn't consistently "burning" or otherwise consuming 20 weights was ford. Subarus, toyotas, kias, gms/chevy, dodges/jeeps, had way too many vehicles coming in at the bottom of dispstick or nothing showing at all. We went through 5w20 synth by the truckload too [f###ing CAFE]. I felt bad every time pumping it in. 5w30 minimum folks! So many get their oil changes every 3k-5k miles thinking they're doing the right thing [following the grade on the oil cap] without a clue they are slowly killing the engine.
I know none of this applies to you all here. Everyone here is anal on their intervals and checking levels and monitoring for consumption and problems. Keep with the watery oils then. Too bad for everyone else I guess, who knows no better. It's a **** shame.
