Remy 20343 Alternator

Remanufactured Alternator for GM Applications

Remy Premium Remanufactured Alternator Part Number 20343 is a 12-volt charging system component built for select GM vehicles that require a 105-amp output. It features an internal voltage regulator, external fan design, clockwise rotation, and a pulley included for direct replacement service.

Compatible With Chevrolet S10, GMC Sonoma, Chevrolet Camaro, Pontiac Firebird, Chevrolet Astro, GMC S15, GMC Safari, Chevrolet S10 Blazer, and GMC S15 Jimmy applications that use a 105-amp charging system. This Remy 20343 alternator is a remanufactured OE-style replacement for Delco/Delphi-based systems.

Key Features

• 105 amp amperage rating for specified charging-system applications
• 12-volt alternator with internal voltage regulator
• External fan configuration
• Clockwise rotation
• Pulley included
• Remanufactured Premium Remanufactured unit
• OE manufacturer reference: Delco/Delphi

Detailed Product Overview

Remy 20343 is built for drivers and technicians replacing a worn alternator in GM trucks, vans, and performance cars from the late 1980s and early 1990s. It is a fitment-specific charging component for vehicles such as the Chevrolet S10 and GMC Sonoma, as well as Camaro and Firebird models that use the correct 105-amp capacity. The part number 20343 is also referenced in interchange listings for several OE and aftermarket numbers, making it easier to match the correct replacement during service.

This part cross-references 1101139 and 10463013 for the same application.

What This Alternator Helps Address

• Battery warning light caused by alternator output loss
• Low charging voltage at idle or under electrical load
• Dim headlights and weak accessory performance
• Hard starting after the vehicle sits
• Charging-system noise or inconsistent electrical operation

Installation Notes and Tips

Verify that the vehicle is equipped for a 105-amp alternator before ordering. Confirm pulley alignment, rotation direction, and electrical connector match the original unit before installation. Because fitment is limited to specific GM applications, compare the original part number and charging-system specifications on the vehicle before replacement. Fits 1987-1993 Chevrolet S10, N/A; Fits 1991-1993 GMC Sonoma, N/A; Fits 1987-1992 Chevrolet Camaro, N/A; Fits 1987-1992 Pontiac Firebird, N/A; Fits 1991 Chevrolet Lumina, N/A; Fits 1991 Oldsmobile Cutlass Supreme, N/A; Fits 1991 Pontiac Grand Prix, N/A; Fits 1987-1990 Chevrolet Astro, N/A; Fits 1987-1990 GMC S15, N/A; Fits 1987-1990 GMC Safari, N/A; Fits 1987-1988 Chevrolet S10 Blazer, N/A; Fits 1987-1988 GMC S15 Jimmy, N/A.

Quality Assurance

Remy Premium Remanufactured parts are remanufactured to OE-style specifications for the listed applications, with Delco/Delphi as the referenced OE manufacturer. This alternator is built for direct-fit replacement in the confirmed vehicle range when the original charging system uses a 105-amp configuration.