The 4L80E is GM's heavy-duty 4-speed - 450+ ft-lbs capacity behind big-block gas and Duramax diesel. Rebuilds need OEM-spec hardware because the failure modes (cracked direct drum, forward sprag, pump leak) are violent. Here's what shop owners rebuilding fleet trucks actually buy.
Heavy-duty friction stack rated for Duramax torque. Includes all O-rings, lip seals, gaskets, thrust washers for the full rebuild. Pair with the specialty tool kit + holding fixture for a complete bench setup.
View on Shopify4L80E weighs 250+ lbs. The case will crack at the bellhousing if you handle it on a standard rebuild stand without the HD adapter. Buy this BEFORE the parts kit.
View on Shopify4L80E TCC failure manifests as a stall the moment you put it in drive. Solenoid AND apply valve replace together - 90% of TCC failures involve both.
View on ShopifyStock 4L80E pressure regulator bore wears at 100K+ miles. Sonnax oversize sleeve kit fixes it permanently. Standard upgrade on every HD rebuild we ship.
View on ShopifyAs an Amazon Associate we earn from qualifying purchases. The links below open Amazon search results in a new tab.
Master Rebuild Kit (Your Transmission) on Amazon →Filter & Gasket Service Kit on Amazon →Shift Solenoid Set on Amazon →Replacement Torque Converter on Amazon →Transmission Assembly Lube (16oz) on Amazon →Specific OE-number deep dives — symptoms, resistance specs, install procedure, and direct-ship pricing.