Sonnax 35801-02K Shift Shaft & Seal Kit GM TH350 TH350C Transmission

The Sonnax 35801-02K is a replacement shift shaft and seal kit engineered specifically for GM Turbo-Hydramatic TH350 and TH350C automatic transmissions. Shift shaft seal leaks are a common issue in these transmissions, and while a seal replacement is often attempted first, the root cause is frequently a scored or scratched shaft that prevents any seal from seating and sealing properly.

Scoring on the shaft surface is typically caused by gritty contamination bypassing a worn seal, or by improper tools used during a previous seal removal. When the shaft itself is damaged, replacing the seal alone will not resolve the leak — the shaft must be replaced as well. This kit addresses both issues simultaneously.

Key Features:

• Complete kit includes replacement shift shaft, seal, and O-ring
• Resolves shift shaft seal leaks caused by shaft scoring or surface damage
• Supplied O-ring can be installed into the shaft groove to help salvage a damaged transmission case
• Zinc-plated finish for corrosion protection
• Direct replacement for OEM shift shaft
• Sold individually

Sonnax is a leading transmission parts manufacturer known for precision-engineered components. The 35801-02K kit provides a permanent solution to chronic TH350 shift shaft leaks, restoring proper sealing and keeping transmission fluid where it belongs.

Interchange / Cross-Reference Part Number: S44991-4K