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.
Sonnax Assembler Darin Dupree carefully packages a shiny new batch of chromoly slip yokes after their final machining operations here in Vermont.
Sonnax Machine Operator Christine Laitres shines up the next batch of Powerglide Smart-Tech® ratio-style servos to achieve that signature clean, sharp shade of blue.
In the Sonnax shop, CNC Operator Jim Yeaton preps a brand new batch of forward clutch hubs.