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
Heads up! We’re taking a few days off for the holidays to spend treasured time with our families and enjoy the holiday cheer.
Sonnax will be closed:
Thank you for all your support. Wishing you a happy, healthy and prosperous New Year!Read More
Sonnax Transmission Company is excited to announce the addition of 13 solenoids and modules to the Rostra Powertrain Controls product group beginning this October. The company has secured these SKUs in an agreement to succeed BorgWarner as the distributor for their OE solenoid supplier, Solero Technologies.
This distribution program represents an important opportunity to support the Sonnax mission: to be the leader in bringing innovative, high-quality drivetrain components to the automotive aftermarket.
Every year, Transmission Digest accepts nominations for the top products and tools in the powertrain aftermarket. Readers vote for their favorites to determine the winners. The results are in: we won 13 top product awards! Thank you all for your trust and support of Sonnax and Rostra products – we couldn’t have done it without you.
Take a look at the winning products here:
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
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.Careers at Sonnax
All of Sonnax product lines are top notch. I use Sonnax on all my builds.
F. Lane, FastLane Racing Transmissions