For those who love driving their classic automatically-shifted Mopar muscle cars – and we mean really driving their cars – one of the very best things you can do is upgrade to an overdrive transmission. The extra gear not only reduces wear-and-tear on your engine and driveline, but reduces heat and of course, allows you to keep up with the flow of traffic.

American Powertrain – one of the leaders in 5 and 6-speed Tremec transmission swaps – has partnered with Gearstar Transmissions to provide a HUGE lineup of available overdrive automatics. Whether you’re pushing 400 or 1,000-horsepower, Gearstar’s lineup of smooth-shifting automatics will have you covered.

These electronically-controlled overdrives ensure crisp shifting under demand, smooth operation even in the worst weather conditions, and a far, far more enjoyable driving experience than what you’re experiencing right now. Kits and applications will vary depending on your application and car’s setup, so you’ll want to call American Powertrain for pricing.

Here’s the original press release:
American Powertrain™, the nation’s leading distributor of TREMEC^® manual transmissions, has now added to its product lineup GearStar™ automatic transmissions for Ford, Chevy, and Mopar. Transmissions include the 4L60E for SBC, BBC and early LT engines, the 4L65E for LS, late LT engines, SB and BB Mopar and Gen III engines, the 4L80E for LS engines, and late model LTs and the 4R70W for Ford small block engines.

Each GearStar transmission is shipped in a protective crate with a Yank billet torque converter, transmission fluid, trans cooler and a factory-style dipstick. Each transmission option is available in various power ranges with 400-1000 ft.-lbs. of torque capacity depending on the model. American Powertrain Pro-Fit install kits are being developed for popular applications and will be announced soon.

Matt Graves, American Powertrain Marketing and Product Manager says, “This is great news for anyone looking to put in a high-performance automatic transmission. We’ve had a lot of calls for automatic transmissions with overdrive and GearStar builds the best automatics in the industry. Just like Tremec, we are proud to offer a great transmission brand. Soon, we will be able to announce specific Pro-Fit install kits, but for now if you are looking to add a high performance automatic, our experienced team will ask all the right questions to ensure the power level you want and recommend a transmission that makes the most sense for your vehicle.”

Power and Torque Level Options:

4L60E
Level 2 – 400 hp/400 ft.-lbs., 1800-2400 stall
Level 3 – 500 hp/500 ft.-lbs., 2600-3600 stall
Level 4 – 650 hp/600 ft.-lbs., 2800-4000 stall

4L65E
Level 2 – 400 hp/400 ft.-lbs. 1600-2400 stall
Level 3 – 500 hp/500 ft.-lbs.., 2600-3200 stall
Level 4 – 650 hp/600 ft.-lbs., 2600-4000 stall

4L80E
Level 2 – 500 hp/500 ft.-lbs., 1800-2200 stall
Level 3 – 600 hp/600 ft.-lbs., 2600-3600 stall
Level 4 – 800 hp/800 ft.-lbs., 2800-3400 stall
Level 5 – 1000 hp/1000 ft.-lbs., 2600-3600 stall

Ford 4R70W
Level 2 – 400 hp/500 ft.-lbs., 1600-2400 stall
Level 3 – 500 hp/450 ft.-lbs., 2600-3200 stall
Level 4 – 750 hp/550 ft.-lbs, 2600-4500 stall

For more information about the new GearStar transmissions available from American Powertrain, visit americanpowertrain.com. To speak with one of American Powertrain’s highly qualified sales technicians, call 931-646-4836.