4T65E

Fits ’94-later 4T60-E. Does not fit 4T65-E Geartronic® or Tapshift® units.

Symptoms:

• Erratic shifts
• 2-3 Shuttle
• No 3rd
• No 4th
• 2nd Gear starts
• Temperature-sensitive shifts

Cause:
The non-anodized valves score and seize in the bore.

Correction:
Sonnax 3-2 manual downshift valve is harcoat anodized aluminum with annular grooves which eliminates surface wear and reduce valve hang-up.

GM 4T60-E and 4T65-E shift valves have changed materials over the years, starting with steel, changing to silver-colored uncoated raw aluminum, and finally anodized aluminum. These units can have a combination of these materials with the silver-colored uncoated raw aluminum being especially problematic due to scoring/scratching and intermittent sticking. The Sonnax 3-2 manual downshift valve eliminates surface wear and reduces valve hang up.These units can have a combination of these materials with the silver-colored uncoated raw aluminum being especially problematic due to scoring/scratching and intermittent sticking. The Sonnax 2-3 shift valve eliminates surface wear and reduces valve hang up.

• Hardcoat anodized aluminum valve combats premature wear
• Annular grooves to center the valves and reduces sticking caused by side loading

SONNAX Installation Instructions