Sierra V-Belt 18-15440 (Replaces Mercury Marine 57-45856) for 4.3L 262 CID V6, 175/185 HP 1985-92

The Sierra 18-15440 V-Belt is a serpentine-style drive belt engineered for 4.3L 262 CID V6 marine engines, covering 175 HP and 185 HP model applications built within the 1985-92 production span, specifically engines falling in the A331455 - D714106 serial number range. This V-belt drives the water pump and other front-end accessories on the engine, keeping cooling and charging systems running under continuous marine duty. Constructed as a V-Belt style belt in grey, it is sized to the exact dimensions of the original equipment belt for this engine family so pulley alignment and tension are maintained without modification.

Installation is a direct fit for the listed 4.3L 262 CID V6 engines, and the belt cross-references directly to Mercury Marine OEM part numbers, so it can be used as a drop-in replacement for a worn or cracked factory belt. Regular inspection and replacement of the drive belt helps prevent water pump failure and overheating, both common causes of engine damage when a belt slips or breaks underway. Each belt ships as a single unit ready to install using standard hand tools and normal belt tensioning procedures.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-15440
• Product Type: V-Belt
• Belt Style: V Belt
• Compatible Engine: 4.3L 262 CID V6 (6-cylinder)
• Horsepower Rating: 175/185 HP
• Model Years: 1985-92
• Serial Number Range: A331455 - D714106
• OEM Cross Reference: Mercury Marine 57-45856, 57-49213A1, 57-93658
• Product Dimensions: 9.3 inches L x 3.3 inches W
• Weight: 0.25 pounds
• Color: Grey
• Country of Origin: Mexico

Fitment

• 4.3L 262 CID V6 engines, 175 HP and 185 HP models, 1985-92, serial number range A331455 - D714106

Replaces (OEM)

• Mercury Marine 57-45856
• Mercury Marine 57-49213A1
• Mercury Marine 57-93658

Frequently Asked Questions

What engines does the Sierra 18-15440 V-belt fit? It fits 4.3L 262 CID V6 marine engines rated at 175 HP and 185 HP, specifically units built within the A331455 - D714106 serial number range, model years 1985-92.

Is 18-15440 an OEM Mercury Marine part number? No, 18-15440 is the Sierra part number; it cross-references to Mercury Marine OEM numbers 57-45856, 57-49213A1, and 57-93658 for direct fit and function.

What are the dimensions of this V-belt? The Sierra 18-15440 measures 9.3 inches in length by 3.3 inches in width.

How much does the 18-15440 V-belt weigh? This belt weighs 0.25 pounds.

What color is the Sierra 18-15440 belt? It is grey, matching the standard appearance of the original equipment serpentine belt it replaces.

Can this belt be used on 1993 or newer 4.3L engines? The 18-15440 is designated for 1985-92 model year 4.3L 262 CID V6 engines within the A331455 - D714106 serial range; it is not specified for engines outside that range.

Is this a genuine Sierra part or an aftermarket copy? The 18-15440 V-belt is a genuine Sierra part manufactured to fit 4.3L 262 CID V6 engines as a replacement for the Mercury Marine equivalents.

What does the drive belt do on this engine? On the 4.3L 262 CID V6 applications covered by part 18-15440, this V-belt drives the water pump and other front-end engine accessories, so a worn or cracked belt can affect cooling performance.

What is included when I order this part? Ordering the Sierra 18-15440 includes one V-belt, sized for the 4.3L 262 CID V6 175/185 HP applications listed.

Where is the Sierra 18-15440 V-belt manufactured? This belt is manufactured in Mexico.

How do I know if my old belt needs replacing? Cracking, glazing, or fraying on the belt surface are signs it should be replaced with a fitting part such as the Sierra 18-15440 to avoid water pump drive failure.

Does the 18-15440 replace more than one Mercury Marine number? Yes, it cross-references to three Mercury Marine numbers: 57-45856, 57-49213A1, and 57-93658.