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.Where to Buy
Enter a Sonnax part number below to view its instructions. For general reaming instructions, click here.
TWO THUMBS UP. I am a loyal user of Sonnax products and they are a company that puts their customers first. Thank you for great products, and I look forward to future products!B. Cole, Toronto, ON
Uniquely designed to fit all '99-later Chrysler 45/545/65/66/68RFE applications – regardless of OE checkball or solenoid configuration.
Easily repair and prevent chronic bushing failure while saving the OE shaft with this unique, patent-pending kit.
Prevent transmission failure due to cracks and wear with high-strength 4140 billet steel direct replacement.
My customers depend on me to keep their vehicles on the road. I depend on Sonnax to help me do that. Thanks Sonnax!S. Moore, Moore's Transmission
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.
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.
Heads up! We’re taking a few days off for the holidays to spend treasured time with our families and enjoy the festivities.
Sonnax will be closed:
Thank you for all your support. Wishing you a happy, healthy and prosperous New Year!
I am a Sonnax fan because no matter if I am rebuilding an everyday transmission or a race transmission, I can trust the quality of the Sonnax parts I choose.C. Lentech, Lentech Automatics
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Sonnax tools save me time, money and come backs, I use them on every rebuild we do in my shop.E. Sebris
Recognized as one of the Best Places to Work in Vermont and recipient of the Governor's Worksite Wellness Award, Sonnax is a leading supplier to the automotive aftermarket. We design, manufacture, test and distribute a wide variety of innovative, high quality products used to remanufacture torque converters, rebuild automatic transmissions, upgrade driveshafts and protect the driveline from over-torque damage.
Sonnax is one of the fastest growing companies in the state of Vermont. Our name has become synonymous with exceptional service, cutting-edge designs, technical knowledge and customer dedication. 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.Careers at Sonnax
All of Sonnax product lines are top notch. I use Sonnax on all my builds.
F. Lane, FastLane Racing Transmissions