Master overhaul kit for the GM 6T30/6T30E six-speed automatic: 14 friction and 14 steel clutch plates plus seals and gaskets for Cruze, Sonic and Encore.
The 6T30 is the six-speed automatic that most small GM front-drivers carry behind the 1.4L turbo, 1.6L and 1.8L engines: the Chevrolet Cruze, Sonic, Aveo and Trax and the Buick Encore and Verano. When one starts flaring between gears, slipping when you get into the throttle, or drops fluid that comes out dark and burnt, the clutch packs and seals inside are worn and a fluid change will not bring them back. This master overhaul kit supplies 14 friction plates, 14 steel plates and the full set of gaskets, lip seals, sealing rings and o-rings for that rebuild, under part numbers B210820A, B210880A and W210881A.
The 6T30 is the light-duty member of the same family as the 6T40 and 6T45, with a matching layout of clutches and a one-way clutch controlled by the TEHCM inside the case. It is sized for small engines, so its clutch packs have less capacity to spare, and a unit that has been driven with low fluid or a slipping pack heats its plates quickly. Each pack depends on two things: lining and steel surfaces in good condition, and seals that hold apply pressure on the piston. A full set of new frictions and steels plus every seal and gasket lets the rebuilder restore both at once, which is the difference between a unit that holds and one that comes back.
Check the fluid level hot first, because a small six-speed run low will slip on its own. Then drop the pan and read the debris. GM Preliminary Information PI0670A covers no reverse and 3rd or 5th slip with P0776 on these units and directs the technician to the 3-5-R clutch before the TEHCM, so steel slivers on the magnet point straight to that clutch and its wave plate. A single solenoid code with clean fluid is a different job; our shift solenoid symptoms guide for the family covers that, and the 6T30 solenoid kit may be all the car needs.
The kit is listed for the GM 6T30 and 6T30E six-speed in the Chevrolet Cruze, Sonic, Aveo and Trax and the Buick Encore and Verano. The 6T30 went through the same 2012-2013 Gen 2 update that GM describes in PI0604C for the whole family, including a revised 4-5-6 clutch, so the plate count can differ by year. Before reassembly, lay your old stack beside the kit and match the B210820A, B210880A or W210881A reference, or send us your year and VIN and we will confirm it. A 6T40 or 6T45 behind a 2.4L engine takes a different kit; see the 6T45E master rebuild kit or the rebuild kit category page.
This kit does not include the torque converter, valve body, hard parts or the wave plate. That last item matters on this family: if your teardown finds a cracked or broken 3-5-R wave plate, replace it and inspect the drum splines before going further. Soak the frictions in Dexron VI, reclutch each pack to the correct count and clearance, reseal the pistons and drums, and refit the pump and valve body gaskets. Check the low one-way clutch while the unit is apart; a worn one causes a slip in first, and the 6T30 sprag clutch replaces it. GM revised the converter seal on units built before February 1, 2013 (PI0950), so install the new one in the kit. Fill with Dexron VI, set the level hot at the check plug and run the adaptive learn. Our rebuild cost guide lists the hard parts that most often add to the job.
| Type | Automatic transmission master overhaul rebuild kit |
| Fitment | GM 6T30 / 6T30E six-speed FWD automatic |
| Common vehicles | Chevrolet Cruze, Sonic, Aveo, Trax; Buick Encore, Verano |
| Clutch plates | 14 friction plates and 14 steel plates |
| Includes | Frictions, steels, gaskets, lip seals, sealing rings and o-rings |
| Part numbers | B210820A, B210880A, W210881A |
| Does not include | Torque converter, valve body, hard parts, wave plate |
| Brand | INGKAN |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
The listing covers the Chevrolet Cruze, Sonic, Aveo and Trax and the Buick Encore and Verano with the small 1.4L, 1.6L and 1.8L engines. Some of those models also used a 6T40 or 6T45 depending on engine and year, so confirm with your VIN.
No. It includes 14 frictions, 14 steels, gaskets, lip seals, sealing rings and o-rings. The wave plate, torque converter, valve body and hard parts are separate. Inspect the wave plate on teardown and replace it if it is cracked.
The kit is referenced to B210820A, B210880A and W210881A. Compare the clutch stack from your transmission with the kit, especially the 4-5-6 pack that GM revised in the Gen 2 update, or send us your year and VIN.
Sometimes. Check the fluid level hot and scan for codes. A solenoid code with clean fluid may only need a solenoid kit or TEHCM work. Burnt fluid, debris and slipping in several gears mean the clutches and seals are worn and the unit needs this kit.
Dexron VI. Fill it, run the engine through the ranges, set the final level at operating temperature through the check plug, then run the adaptive learn so the TCM adjusts to the new clutches.
