Dealership, then Firestone of Sears. I avoid Pep Boys for more than just tires. A visit or two to wait room and service desk reveals too many other customers complaining.

If a small mechanic shop is nearby? Try him.

Well, if price isn't a problem I would choose the dealership. I don't know what kind of diagnosis you're looking for but usually a simple multi-point checkover is free.

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Between the 2, I'd personally lean towards Firestone, but Brian has a good point. Shop around.

I dont care for either, i would check out any mom and pop shops around town, both of those places charge way too much and most are not real mechanics but just oil changers.

So I was thinking of getting my car diagnosed and repaired and I was thinking of 3. Firestone Complete Auto Care, Pep Boys, or the actual dealership. Which one would be better to go too, I want a full diagnostics of my car from engine to suspension and things in between. I just want to know which one does quality work but with also a reasonable price.