National Transmission is conveniently located at 4420 Griggs Road in Houston TX. We are a family-owned auto and transmission repair shop that has been offering top-quality automotive repair services to the Harris County community since opening our shop in 1979. Our auto repair shop is open Monday to Friday from 8:00 AM to 6:00 PM and closed weekends. We can be contacted during business hours by telephone at 713 741 5344. Below you will find a map of Houston showing our shop's location and the ability to get door to door directions to our repair shop's location. Please feel free to request a price quote or schedule an appointment for a vehicle repair or service any time using our online forms.