Looking for new or used cars in Orange County? Tustin Buick GMC has been a family-owned business since 1954, and in that time, we've built up incredible customer loyalty, both for auto sales and in our world-renowned H1 service center. We carry all the latest GMCs and Buicks as well as many great certified pre-owned vehicles. If you are looking for used cars in Orange County, Irvine and all of the Inland Empire, you know you can count on Tustin Buick GMC.