Mad Dog Transmissions of Alpharetta

Mad Dog Transmissions of Alpharetta is a transmission shop in Alpharetta, Georgia, specializing in high-performance and heavy-duty transmission rebuilds, repairs, and upgrades. The shop serves drivers across Forsyth County and North Atlanta, offering services for GM transmissions including the 700R4, 4L60E, 4L80E, and modern 8- and 10-speed models, as well as custom builds up to 1,500 horsepower. They provide full diagnostics, fluid and filter service, torque converter replacement, shift kit installations, and transmission removal and replacement. With a focus on GM vehicles, they also service Ford, Dodge, and other American makes, and offer nationwide shipping with a one-year unlimited-mile warranty on all work. The shop has a 3.90 rating based on customer reviews.

Founded in 1986, Mad Dog Transmissions is led by second-generation transmission builder “Mad Dog” Lou, a former NHRA drag racer who learned his craft in his family’s shop. The shop’s approach is rooted in correcting known factory design flaws, such as weak sun shells, slipping clutch drums, and failing plastic accumulators, before installing high-energy components. Every transmission is rebuilt from the ground up, with all wear parts replaced, and tested on a dyno before shipping. They specialize in performance builds ranging from Level 1 (300 HP) to Level 5 (1,000 HP), with custom capabilities extending to 1,500 HP. Their expertise includes 4L60E, 4L80E, 2 Speed Powerglide, and trans-brakes for bracket racers, and they maintain a fully functional shop in Alpharetta for local service and installation.

The business is located on Union Center Drive in Alpharetta, Georgia, situated about 0.2 miles from DeSana Middle School and 0.3 miles from McFarland Parkway. It lies approximately 0.4 miles from Union Hill Road and 0.5 miles from Forsyth County Fire Station #14. Brandywine Elementary School is about one mile away, and Turner McDonald Parkway is just over a mile north.

Mad Dog Transmissions is known for its long-standing reputation in performance transmission engineering, built on decades of hands-on experience from a racing background. Their commitment to durability, dyno-tested precision, and factory flaw correction has made them a trusted name for both street and strip vehicles. The shop’s ability to handle everything from daily drivers to race-prepped builds underscores its deep expertise in GM and modern automatic transmissions.