The complaint
A 2015 Chevrolet Equinox equipped with the 3.6-liter engine and GM 6T75 transmission has complaints of a delayed engagement into drive and slips in first gear.
The cause
A generation one 1-2-3-4 Clutch Apply Piston was installed into a generation two transmission. The generation two 1-2-3-4 Clutch Apply Piston apply fingers are .147 in. taller than the generation one piston. This created too much clutch clearance for the clutch pack to effectively hold.
The correction
The generation one 1-2-3-4 Clutch Apply Piston apply finger height is .638 in.; refer to figure 1, above.
The generation two 1-2-3-4 Clutch Apply Piston has a apply finger height of .785 in.; refer to figure 2. For generation two, the 1-2-3-4 friction were reduced in thickness to .058 in. Generation one 1-2-3-4 friction plates are .061 in. thick.
Generation two components were used selectively with the start of the 2013 model year. All 2014 and later models should have generation two components.
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