Input shaft failure is a common problem in performance and heavy duty GM 4L80-E and 4L85-E transmissions. Sonnax heavy duty input shaft 34670-01 is manufactured from high strength 300M with proprietary heat treatment and post-heat treat processing for exceptional performance, durability and value.

O.D. carrier spline where shafts typically fail is greatly improved by eliminating OE undercut plus the addition of extra spline material at the major diameter that fills the gap at the root of the internal O.D. carrier spline.

This shaft is recommended for applications up to 1,000HP.

• Advanced torsional design with spline and cross-hole refinements for additional strength
• Hobbed O.D. carrier spline eliminates deep undercut where other shafts fail
• Extra spline material for additional strength