I had a fuel delivery problem with my 2004 GMC Sierra Duramax that was causing the engine to surge at low RPM. A mechanic I trust couldn't figure out the problem, and referred me to Aus-Tex. They were able to diagnose the issue in just a few hours, and while the repair was expensive, gave me a discount on the labor.Everyone was prompt and friendly, but most impressive was the communication Teresa, the office manager, maintained with me throughout the process. She texted me with regular updates, and sent me photos of what the tech found during the diagnosis, so I could follow along and evaluate the problem on my own end. Great help, and I'll be going back.