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American Powertrain

Listing Information:


America Powertrain

2250 Stock Creek Blvd, Rockford, TN 37853
Call: 865.609.8187
Fax: 865.609.8287
Monday – Friday: 8AM – 7PM
Saturday: 8AM – 4PM


We are the Nation’s Leading Supplier of Engines,
Differentials, Transmissions and Transfer Cases
Get a Free, No Obligation Price-Quote Today!


American Powertrain exists to help muscle car owners equip their cars with modern drivetrain technology, offering overdrive transmission systems, hydraulic clutch kits and a wide range of drivetrain related parts from diff to block.

Since American Powertrain opened for business we have quickly become the world’s largest TREMEC dealer. Our installation parts and systems are proudly made right here in America for unmatched quality.

Our staff of highly experienced enthusiasts has years of experience helping car owners and builders make the right drivetrain choices.



Get your shift together

Every project is different. From model and engine choice to driving style and rear end ratio every customer wants to make the best choices to make the car they are dreaming of a reality. Every American Powertrain ProFit™ transmission system is sold with your project goals in mind.

From Corvette to ‘Cuda, Mustang to Monte Carlo and every muscle car, street rod, custom or classic truck in-between American Powertrain systems are engineered to help you get your shift together the right way for miles of smiles on the street, strip, road course or wherever your dreams take you.

We know how important this is to you. That’s why we ask the right questions and then build you the best fitting, easiest to install and most comprehensively supported aftermarket powertrain solutions anywhere.



We are more than a transmission company, much more…


Hydramax Clutch Systems Bellhousings & Adapters Crossmembers Drive Shafts

Rear Axle Assemblies White Lighting Shifters Transmissions Kits Transmissions

EZ Electric Power Steering Science Friction Flywheels


If you have a 4, 5 or 6-speed or even an automatic, American Powertrain has great parts to help you finish your project right.
We offer:


QuickTime Scattershields
SFI rated for hundreds of manual and automatic applications at the best prices anywhere.
AP Aluminum Bellhousings
Made in the USA to very exacting standards for GM, Ford and Mopar.
Science Friction Clutches & Flywheels
Our own exclusive line of top shelf performance parts for all 4, 5 and 6-speeds.
HYDRAMAX Hydraulic Systems
For 4-speed, 5-speed and 6-speed applications; the best selling hydraulic conversions in the industry.
X-Factor Crossmembers
High strength aluminum cross members for almost any manual or automatic transmission.
Complete Engines
From our wide range of trusted engine builders and crate programs.
Axle Assemblies
12-bolt and Ford 9” assemblies hand built in NASCAR country for your GM or Ford complete and ready to bolt in.




We carry over 3000 rebuilt vehicle engines, in stock throughout our distribution network, allowing us to yield a 1-3 day delivery time to most of the continental U.S..

All of our remanufactured car & truck engines are delivered completely assembled with gaskets and an oil pump. The replacement engines supplied, are fully updated utilizing all known OEM & aftermarket repairs, to correct performance problems with the engine and ensure that you receive an improved product over the original factory design. In some cases our engines are available with oil pans, timing covers & valve covers, depending upon applications.

When complete, all of our replacement engines are fully tested to confirm proper operability at installation. Package this with up to a 7 YEAR Million-Mile (No-Fault) parts & labor warranty – and you can see that we are offering our customers the highest quality rebuilt auto & truck engines, at the best price with the best service, and greatest warranty available in the industry!



Support after the sale

Many companies help you right up until they have your money, but American Powertrain is there for you if you need help after the sale with our Customer First™ Extended Hours tech line, 2-year warranty on almost everything, great installation instructions and a complete library of online videos to help along the way.

If you have a wrench in your hand we are here to help; nights, weekends and even on holidays. We feature the TREMEC T5 and TKO in our 5-speed systems and the TREMEC Magnum in our 6-speed kits.

Many of these transmissions are modified by American Powertrain to fit your specific make and model with little or no modification to your car.
We also offer Xtreme power and rpm upgrades on each of these transmissions with power ratings up to 1100ft-lbs.

Xtreme upgraded transmissions are available as bare units or as part of our comprehensive ProFit™ Kits with every component you need to convert from manual or automatic to a modern overdrive transm