No one knows transmissions & torque converters like

Sonnax designs, develops and manufactures the highest quality aftermarket automotive products. We are the world’s largest full-line supplier of torque converter parts, and offer transmission and specialty driveline components through a global network of parts distributors.

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Latest News

December 01, 2021

Holiday Giveaway – Enter Now Through Dec. 31

Enter to win one of three $100 Visa gift cards plus a cool Sonnax swag bag! 

Here's how to enter: You can either enter on Facebook, or you can send an email to [email protected] telling us one reason why you're a Sonnax fan. It’s that easy!

You have until 11:59 p.m. on Dec. 31 to submit your entry. Three lucky winners will be chosen at random and announced on Friday, Jan. 7.

Good luck and Happy Holidays from all your friends at Sonnax! 

Official Rules: No purchase necessary. Open to U.S. residents aged 18 and older. One entry per person. Except where prohibited, participation in the Sonnax giveaway constitutes winner's consent to Sonnax use of winner's name and comment for promotional purposes in any media, worldwide.

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August 12, 2021

Sonnax & Rostra Powertrain Controls: Two Brands, One Company

Sonnax Transmission Company is excited to announce a recent reorganization, integrating Rostra Powertrain Controls into the company’s Vermont- and North Carolina-based Sonnax operations. This concludes several years of internal moves aligning teams and resources to better serve the transmission aftermarket. Both the Sonnax and Rostra brands have been part of Marmon Holdings, Inc. since 2018, with Steve Boyer leading both teams as President since 2020.

“Through this integration, Rostra and Sonnax will become a single, transmission-focused organization,” said Boyer. “This new structure will synchronize our product development efforts, reduce time to market of new products and allow us to make improvements in quality and delivery to our shared customers.”

Boyer said several internal promotions were made to support the alignment of both brands under Sonnax Transmission Company:

Maura Stafford is appointed company Vice President of Transmission Products. Stafford and her team manage product groups focused on hydraulic and electronic transmission components, solenoids and remanufactured valve bodies.

Steve Jaussaud continues as company Vice President of Product Line Management, guiding development of torque converter, high performance, driveline and mechanical transmission components. Jaussaud also manages the torque converter product line, a responsibility he assumed in late 2020.

Beth Houder is appointed company Vice President of Marketing & Communications, leading marketing efforts and the continued development of both brands in the aftermarket industry.

Mark Kaplan serves as company Vice President of Sales, assuming sales management for Sonnax and Rostra. He is joined by Seth Baldasaro, Director of Strategic Accounts, and Tony Diorio, National Accounts Manager.

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February 11, 2021

Get a New Sonnax Beanie – Now Available for a Limited Time Only

Stay warm this winter with an official Sonnax Performance beanie from the online fan store!

Available for a limited time only. Click here to order now

 

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Join an exciting front-line team focused on developing and delivering the best products in the industry, a team whose imagination, hard work and results are rewarded.

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.

Our 200+ employees proudly serve the automotive aftermarket with the Sonnax and Rostra Powertrain Controls brands, and strive to further the company’s reputation for excellent service, technical knowledge and customer dedication.

Sonnax Transmission Company headquarters is in Bellows Falls, Vermont, with production facilities in Laurinburg, N.C. and technical development centers in California, Georgia, Indiana, Missouri and Wisconsin. Rostra Powertrain Controls’ production facility is in Laurinburg, N.C.

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