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.

Where to Buy

View Sonnax Part Instructions

Enter a Sonnax part number below to view its instructions. For general reaming instructions, click here.

Latest News

November 12, 2019

Sonnax Closed for Thanksgiving

Sonnax will be closed Nov. 28-29 in celebration of Thanksgiving. Wishing you a very happy holiday filled with great food, fun and company!

August 27, 2019

Sonnax Closed on Labor Day

Sonnax will be closed Monday, Sept. 2, in observance of Labor Day. Wishing you a safe, happy holiday! 

July 23, 2019

Sonnax TASC Force Meets in Omaha

The Sonnax Technical Automotive Specialties Committee (TASC) Force recently met in Omaha, Nebraska to discuss emerging market needs, ideas for new parts and other hot-button issues. Forty trusted professionals attended this important meeting, representing 15 companies from the U.S and Canada, bringing an abundance of exciting ideas for new aftermarket solutions.

In welcoming the group, Sonnax President Steve Boyer commented on the investments Marmon has made in the year since acquiring the company, specifically on inventory and human resources. “We want to make sure Sonnax has the appropriate people in place to design, produce and deliver what you need, when you need it. We are also investing in our warehouse this year so we can get parts out even faster.”

This year’s gathering included a lot of great discussion about new product ideas and opportunities as well as a tour of Certified Transmission’s Omaha-based headquarters. More than 75 new product ideas were submitted, of which the group then votes on, based on which are most critical to develop to support the industry at-large. “The depth of knowledge of this group, and their enthusiasm for helping us develop fixes for problems is truly inspiring,” said Maura Stafford, Sonnax Transmission Specialties Product Line Manager.

Independent TASC members work for large shops, small shops, volume transmission and volume valve body rebuilders. Alongside Sonnax engineers and specialists, they are helping to develop repairs which will be used by their companies and by the rest of the transmission aftermarket. Their efforts help provide answers and repairs for the entire industry. Everybody wins.

Check out photos from the event on the Sonnax Facebook page


Read More
View News Archive

Upcoming Events

Sign up today for Sonnax enews!

You’ll be the first to know about:

  • New product releases
  • Free tech resources
  • News and events
  • Special updates

Select your topic(s) of interest and receive only the information that’s important to YOU.


Enjoy a rewarding career and relaxing quality of life
in beautiful Southern Vermont.

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