I highly recommend the Annandale Citgo gas station at 7131 Columbia Pike, not too far from Kilroy's. It's run by a crew of Vietnamese who are extremely efficient. They fix your car right now. Literally, just tell the front desk what you need, and the manager snaps his fingers and your car is swarmed by a team of skilled Vietnamese mechanics. They did my front brake pads on my Civic last time in like 10 minutes, tag team style. They also have a brake disc lathe and will resurface your discs for cheap.
I asked the manager once "how do you fix these cars so efficiently", he said "this is how we compete with the dealer. The dealer wants you to make an appointment days in advance and wait a long time. We do it right now. That's how we compete." There are some old timer Vietnam Vets who take their old American Iron there and swear by them. They loved my 40. Reminded them of the old days back in Nam.