Shiftvalve 4T60E 4-3 manual
Material: Anodized Aluminium
OE 4T60-E shift valves have changed materials over the years, starting with steel, changing to silver-colored uncoated raw aluminum, and finally anodized aluminum. 4T60-E 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. It is highly recommended to replace all raw aluminum shift valves with the Sonnax hard-coat anodized replacements. These are drop-in replacements and do not require any machining. Valves also have applications in 4T60-E and 4T65-E.
2nd Gear starts
The non-anodized valves score and seize in the bore
These valves are hard anodized with annular grooves which eliminate surface wear and reduce valve hang-up.
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