This is my spot in Walnut Creek area for oil changes on my 2009 Infiniti G37. I typically do oil changes myself, but I've since been garage-less after obtaining this car, so I don't have anywhere to work on it alone and I don't very much like paying exuberant prices at the dealership just for a quick service. I don't very much trust many "quick lube" places either, so I feel much better coming to Oakmont when I don't have an opportunity to work on my car myself. A good middle-ground my wallet can be happy with, I know my car will be treated with care, and I sleep better at night knowing my money is going to local business/community and not some huge chain/corporation. Most recently I went in for a Check Engine Light that was pulling a code P2A00 (O2 Sensor / Bank 1 Sensor 1) causing me to fail smog test. The owner James highly recommended that we did a full diagnostics check, because it was absolutely possible there was nothing wrong with the oxygen sensor at all even though that was the engine code being pulled. Me coming from old 90's Hondas/Acuras (which seemingly have about a third of the sensors today's cars have), I was certain there was no need for an extra diagnostics check and we just needed to replace the oxygen sensor and everything will be fine. Paid for it and I thought everything was good. However the same P2A00 (oxygen sensor) check engine light came back two days later. Brought the car back and this time I agreed to do the diagnostics check like James suggested the first time around. A smoke test on the exhaust system was part of that check and turns out one of my catalytic converters had a crack, causing conflicting readings between the oxygens sensors, but the car was simply saying "the first O2 sensor has an issue". So we replaced the catalytic converter and the check engine light never came back (which has now been about month before writing this review). I should have listened to James from the get go! I essentially paid for two expensive parts in the end when I only needed to pay for one expensive part. ***Long story short — Listen to James if he suggests you do the diagnostics check. *** So many highly-sensitive components in today's cars that are all working together simultaneously. Its easy to quickly assume its as simple as replacing just one particular part, all because a code reader says "there is an issue here". Thanks again for taking care of this! I am due for an oil change in the coming weeks, so see you guys again soon.