4T65E Transmission Master Rebuild Kit with Pistons

Master rebuild kit for the GM 4T65E four-speed front-wheel-drive transaxle, part number T06200C. It covers 1997-up Buick Century and Rendezvous and Chevrolet Impala, and 1997-2007 Monte Carlo and Uplander, behind the 3.1L, 3.4L, 3.5L, 3.8L and 3.9L V6 engines. The same transaxle shows up under Grand Prix, Bonneville, LaCrosse, Regal, Aztek, Montana, Venture, Silhouette and Terraza, so the kit fits well beyond the models printed on the box.

What separates this from a plain overhaul set is that the molded clutch pistons and the pan filter are in the box along with the frictions and steels. On the bench that means you strip the unit, pull the forward, direct, second and reverse packs, and reline every one of them with new frictions and new steels instead of reusing glazed plates. The new pistons go in as you rebuild each drum, and the full gasket, lip seal, O-ring and Teflon sealing ring set covers the pump, channel plate, case and servo bores when you reseal on assembly.

These are the parts that fail on a high-mileage 4T65E: burnt forward and direct clutches that show up as slipping in third and fourth or a flare between gears, cut sealing rings that bleed line pressure and set pressure-control codes, and a hardened, leaking case-to-channel-plate gasket. Fluid-starved units from a plugged filter come apart the same way, so the filter belongs in the rebuild, not in a later service. You supply fresh Dexron-VI and any hard parts your teardown turns up.