GM 6T40 6T45 4-5-6 Clutch Drum 4-Ring Piston 10-Hole New Rings Cruze Sonic

GM 6T40 6T45 4-5-6 Clutch Drum 4-Ring Piston 10-Hole New Rings Cruze Sonic

Used OEM unit pulled from an inspected donor transmission, cleaned and visually inspected before listing. Photos show a representative unit of this exact part and variant — see the fitment and casting notes below to confirm your match.

• SKU: G-6T40-DR-U-03
• Includes: You receive one good used 6T40/6T45 Generation 1 3-5-Reverse / 4-5-6 clutch drum — the 4-sealing-ring hub version with 36 outer lugs, sized for the 4-friction 4-5-6 pack — supplied with a NEW sealing ring kit for the hub. NOT INCLUDED: 4-5-6 friction plates and steels, 3-5-R clutch plates, the clutch backing plate, the drum-to-input-shaft snap ring, the wave plate, the input shaft, the stator support, and any bushings. The backing plate and snap ring in particular are excluded, and they are the exact two parts tied to the mid-2010 design change, so plan to reuse your matched set or source the correct design separately.
• Warranty: 30-day return-or-replace after delivery
• Shipping: UPS Ground from our Tennessee warehouse, 2 business day handling

OEM / interchange references (verify against your casting/tag):

• 46550AB

Fits (engine/year matters — read carefully): This is the Generation 1 3-5-Reverse / 4-5-6 clutch drum for GM's 6T40 (RPO MH8/MHB) and 6T45 (RPO MH7/MHC) six-speed transverse automatics, identified by its 4-sealing-ring hub, 36 outer lugs and 4-friction 4-5-6 clutch pack. Gen 1 production covers roughly the 2008-2011 model years, which in the US market means: 2008-2011 Chevrolet Malibu 2.4L I4; 2009 Saturn Aura 2.4L I4; 2009-2010 Pontiac G6 2.4L I4; 2010-2011 Chevrolet Equinox 2.4L I4 and 2010-2011 GMC Terrain 2.4L I4 (both 6T45); 2011 Chevrolet Cruze 1.4L turbo (LUJ) and 1.8L (LUW); 2011 Buick Regal 2.4L I4; and 2011 Buick LaCrosse 2.4L I4.

Important: There are two separate traps, and the second one catches even experienced rebuilders. TRAP 1 — Gen 1 vs Gen 2, the ring count. Before ordering, count the sealing rings on the hub (the "ring tower") of the drum you pulled out. This drum has FOUR rings. The Gen 2 drum has only THREE — GM's own bulletin PI0604C describes the change as "Removal of one 3-5-Reverse and 4-5-6 Clutch Fluid Seal Ring." Cross-check two more ways: count your 4-5-6 friction plates (Gen 1 uses 4 frictions plus a wave plate; Gen 2 uses 5 frictions and no wave plate), and count the holes in the hub area where the support rides (this Gen 1 drum has 10 smaller holes; the Gen 2 version has 9 larger ones). If you put a 3-ring Gen 2 drum into a Gen 1 unit, the missing fourth ring and the missing fluid-dam inner seal mean the compensator regulator circuit no longer regulates and sits wide open — you get a low-pressure complaint, typically falling out of gear at a stop.

Before you order: confirm your transmission code and casting/part numbers. Not sure? Message us through eBay with your VIN or transmission tag and we will confirm fitment the same business day. Rebuilder shops — ask about volume pricing. We stock transmission hard parts by family and can hold inventory for scheduled builds.