CHEVROLET,GMC LV3/LV1(4.3L)V6 Crankshaft – OE 12691777

Overview

This is a new LV3/LV1(4.3L)V6 crankshaft listed for CHEVROLET,GMC applications, carrying OE references 12691777. It suits rebuild and repair work on engines with damaged journals, thrust surfaces or a broken crank, and is supplied as a single unit.

Engine application

• Engine code: LV3/LV1(4.3L)V6
• Listed for: CHEVROLET,GMC
• OE references: 12691777

How this part fails

Because the crankshaft sits at the centre of the rotating assembly, wear shows up as noise and pressure loss rather than a sudden failure. A knocking bottom end, oil pressure that falls away when hot, glitter in the drain oil or a crank that no longer turns freely all point to journal damage. Once a journal is scored or oval, grinding undersize is the only repair and a replacement crank is often the simpler route.

Specifications

Fitment checks before ordering

Do not order on vehicle model alone. Check the engine code plate reads LV3/LV1(4.3L)V6, then match the OE number stamped or printed on your existing crankshaft against the references listed here.

Rebuild notes

Plan the rebuild around measurement, not assumption. Verify journal diameters and taper, confirm thrust clearance, and fit bearings sized to the crank actually supplied. Replace the rear main seal, clean the oil galleries and check the oil pump pickup while the sump is off. Torque figures and sequence should come from the engine manufacturer's manual for your engine code.

What is included

The listing covers the crankshaft only. Main and big-end bearings, rear seal, flywheel bolts and gasket sets are separate items and should be ordered to suit the rebuild.

Availability and warranty

The listing does not publish a stock quantity, so availability is confirmed by the supplier at order rather than shown here. The current Alibaba listing quotes delivery by Dec 28. The manufacturer states a 1 year or 10,000 KM, whichever comes first warranty on this listing.