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Company Overview

Sonnax Transmission Company is an industry leader in the cutting-edge design, manufacture and distribution of the highest quality products to the automotive aftermarket, commercial vehicle industries and industrial sectors utilizing drivetrain technology. Sonnax Transmission Company, a Marmon/Berkshire Hathaway company, serves the aftermarket with both the Rostra Powertrain Controls and Sonnax brands.

After decades of serving the transmission aftermarket as standalone companies, Sonnax and Rostra Powertrain Controls integrated in 2021 to become a single, transmission-focused organization.

What sets us apart from the competition is our passion for quality and innovation. This passion exhibits itself in our long-standing philosophy to address the root cause of a problem, and not just treat the symptoms. In striving to discover what causes common transmission and converter problems, we meld new ideas, materials and state-of-the-art testing to ensure our parts will restore OE performance, or make it better-than-new.

Rostra Powertrain Controls’ production facility is in Laurinburg, N.C., with a technical development center in Grand Rapids, MI. We are recognized globally for our exceptional quality and customer service and proudly hold ISO-9001:2015 and IATF-16949:2016 quality certifications.

For more information on Sonnax Transmission Company and Sonnax products, please visit

Our Policy: Continuously improve our products and services in order to deliver a defect-free product on time.



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