6T50 Clutch Drum 2008, new and ready to install. Fits the 6T50. Ships fast from the USA.
The 6T50 is the highest-torque member of GM's front-drive six-speed family, the one GM fitted to bigger engines in models like the Chevrolet Captiva, Buick Regal, Verano and Malibu. When one of these upshifts into third and then refuses fourth, or a rebuild finds the top-gear drum with chewed lugs, this is the part to replace. It is a new aftermarket 4-5-6 clutch drum assembly, part D46550AAK, listed for 2008 and later 6T40, 6T45 and 6T50 units. It includes the drum, a wave plate, a pressure plate and a snap ring. The drum has 36 outer lugs and is described as a 4-clutch drum.
Like its smaller siblings, the 6T50 shifts clutch-to-clutch, holding two clutches for every forward range. The 4-5-6 clutch is the common member of the three top gears. Fourth is the 4-5-6 clutch working with the 1-2-3-4 clutch, fifth adds the 3-5-R clutch, and sixth adds the 2-6 clutch. Gearboxlist gives the 6T50 ratios as 1.446 in fourth, 1.000 in fifth and 0.746 in sixth, so every mile of highway driving runs through this pack. The drum's outer lugs carry the steel plates, the wave plate softens the apply, and the pressure plate and snap ring set the stack. Because the 6T50 is rated for about 350 Nm, more than the 6T40, the 4-5-6 pack works hard in fifth and sixth with a full load or on long grades.
Rule out the other common failure first. Gearboxlist and GM bulletins both point to the 3-5-R wave plate as the known weak spot in this family. When that plate breaks, reverse, third and fifth go first, usually with P0776. If reverse still works and the trouble starts at fourth, the 4-5-6 pack is more likely.
Check the fluid level and condition first, then read the codes. Our won't shift into overdrive guide walks through the checks for a unit that stops at third. The 3-5-R wave plate failure guide explains how to tell that failure apart before you tear down. With the unit out, look at the drum lugs, spline teeth and sealing ring bore under good light. Air-check the 4-5-6 piston, because a leaking seal can look like a bad drum.
GM's bulletin PI0604C lists the 6T50 (RPO MHK and MHJ) among the units updated to the Gen 2 design for 2012. Gen 2 revised the 4-5-6 clutch piston, return spring and fluid dam, moved the piston outer seal, and changed the 4-5-6 friction count to five. This drum is described as a 4-clutch unit, so it suits a four-friction stack. If your transmission is a 2012 or later Gen 2 unit, compare your old drum, lug count and plate stack before ordering. Some 2012 vehicles, including the Captiva Sport 3.0L, stayed on Gen 1. Send us your year, VIN and a photo of your old drum if you are unsure. Our 6T40 family identification guide shows how to read the tag. Other 6T50 parts are listed on our hard parts page.
| Fits | 6T50 2008 |
| Part type | Clutch Drum |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Yes, the same D46550AAK assembly is listed for 2008 and later 6T40, 6T45 and 6T50 units. The 6T50 is the higher-torque version of the same family. Match your old drum's lug count and stack before installing.
Possibly, but check first. GM's Gen 2 update changed the 4-5-6 piston, return spring and fluid dam, and the friction count to five. This drum is described as a 4-clutch drum. Compare it to your old drum, or send your year, VIN and a photo.
The drum, a wave plate, a pressure plate and a snap ring. Friction and steel plates, piston seals and sealing rings are not included, so plan on a rebuild kit.
Probably not. Losing reverse, third and fifth, often with P0776, points to the 3-5-R clutch and its wave plate, the best-known failure in this family. The 4-5-6 drum is the suspect when fourth, fifth and sixth are missing but reverse still works.
DEXRON VI. Gearboxlist gives about 8.2 L total capacity and about 5 L for a drain and fill. Set the final level hot at the check plug.
Yes. After a rebuild, clear the adaptive values and run the transmission adapt procedure with a scan tool. This lets the control module learn the new clutch fill times.
