June 22, 2023
Main shaft failure is a common problem in performance and heavy duty GM TH400, 4L80-E and 4L85-E units. Sonnax heavy duty main shaft 34672-01 is manufactured from high strength 300M with proprietary heat treatment and post heat treat processing for exceptional performance, durability and value. This shaft is recommended for applications up to 1,000HP. For extreme horsepower applications, see Sonnax extreme duty main shaft 34672-05 — the most durable 1” main shaft available.