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.

Featured Products Where to Buy
34200 40k web

4L80-E, 4L85-E

Smart-Tech® Overrun Clutch Valve Kit 34200-40K

Fits units '97-later.

76654 01k

4R70E, 4R70W, 4R75E, 4R75W, AODE

Smart-Tech® Forward Clutch Drum 76654-01K

Compatible with ISS-equipped and non ISS-equipped applications

Gm cc 17

300mm (4L60-E)

Front Cover GM-CC-17

For use in TMBX converters only.

Ho 90 5g


Impeller Hub HO-90-5G

Also fits Saturn VUE.

Latest News

July 12, 2018

Sonnax Job Fair - July 24

Take the first step toward starting your new career at our upcoming job fair! We are currently hiring for permanent, full-time positions as:

  • Product Support Reps
  • Warehouse Workers
  • Packagers
  • CNC Machine Operators
  • Machine Operators
  • Buyers
  • Packaging Inspectors, and more!


  • Medical/dental/vision insurance
  • Group life/supplemental insurance
  • 401(k) retirement savings plan
  • Paid holidays (10)
  • Vacation and sick pay
  • In-house gym
  • Employee discount program
  • Tuition reimbursement, and more!


  • 18 years of age or older.
  • Must have High School Diploma.
  • Must be authorized to work in the U.S.
  • Physical demands including lifting, pushing, and pulling up to 50 lbs.
  • Prior industry experience is preferred.
  • Background check and drug screen are required for employment.

Register to Attend Today!

We are an Equal Opportunity Employer

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July 03, 2018

Sonnax Closed for 4th of July

In honor of Independence Day, Sonnax will be closed Wednesday, July 4. Normal business hours will resume Thursday, July 5. Wishing you a safe and happy holiday!

May 29, 2018

Sonnax Hosts Annual TASC Force Meeting

The Sonnax TASC Force recently got together for its annual meeting to discuss new product needs for the market. The meeting was held May 18-19 at the Sonnax New Jersey facility and the Warwick Rittenhouse Square Hotel in Philadelphia, PA. In attendance were 29 TASC members, representing 17 shops from six different countries.  

The meeting kicked off with a tour of Sonnax following a briefing by plant manager Mark Spaseff and remanufactured valve body product line manager Maura Stafford.  The tour focused on six major stations in the plant: receiving, core prep, reaming, building, testing and shipping. The re-occurring topic heard at all stations was the Sonnax commitment to safety, quality, delivery and continuous improvement. “We have been working hard to improve our products and service and are very excited to share our process improvements with the TASC Force,” said Spaseff.

After the tour, the group returned to the hotel where they were welcomed by Sonnax Transmission Company president Steve Boyer.  Boyer thanked everyone for attending the meeting and expressed his excitement to be there as he’s heard so much about what TASC means to Sonnax, and how it affects the new product development needs of the industry.

Meeting topics included new product suggestions, Sonnax quality, and industry trends that the automatic transmission aftermarket is facing today.  

Former President & CEO Tommy Harmon
Former President & CEO
Tommy Harmon

This year, more than 90 new product ideas were submitted, of which the group then votes on based on their importance to rebuilding today’s transmissions. Sonnax Vice President of product line management Steve Jaussaud noted the progress that his team has made; nine out of the 15 TASC picks from previous meetings are now available from Sonnax, and the other six are currently in development for future release.

A highlight of the TASC meeting is always the Friday night dinner where members have the opportunity to get together to discuss business and reminisce about meetings past. This year was especially notable when Steve Boyer presented former president and CEO Tommy Harmon with a framed Sonnax license plate from the traveling tech van. Boyer thanked Tommy for his vision and dedication to the TASC Force, and committed to keeping the mission alive in the future.

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Upcoming Events

ATRA Technical Seminar

1717 Disneyland Dr., Anaheim, CA

August 18, 2018, 8:00AM - 4:00PM

Learn More

SEMA Show 2018

Las Vegas, NV

October 30, 2018, 9:00AM - 4:00PM

Learn More

ATRA Powertrain Expo

Las Vegas, NV

November 01, 2018, 7:00AM - 5:00PM

Learn More
See All Events

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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