A number of years ago, I purchased a new car with a factory turbo.
The magazine articles (pre-internet) contained conflicting information; and local mechanics I asked merely parroted this conflicting information.
I decided to call the manufacturer for guidance.
The secretary (no answering machine
) directed me to the engineer who designed the engine, and I was given some really interesting information concerning oil for turbo engines. Virtually everything being suggested by the magazines and local mechanics was unsuitable!
I followed the engineer's advice on this vehicle, and another of the same I later purchased used. While I still have the vehicle I purchased new, we sold the used vehicle with more than 200k miles, and the engine and turbo still functioning well.
Maybe a call to Chevrolet zone might prove fruitful.
To quote a good friend (Tom V.) who posts on another forum: "Engineers do things for a reason".
Jon.
