Oregon 3PK Mower Blades Replacement for Exmark 103-6403-S 60" Deck Lazer Z S/N 540,000 & Higher

What It Is

This is a set of three aftermarket mower blades designed to replace the OEM Exmark 103-6403-S blades on 60" Exmark Lazer Z mowers with serial numbers 540,000 and higher. They are ideal for residential and commercial mowing on medium to large lawns.

Fitment & Compatibility

Before purchasing, verify these critical points:

• Deck size: Must be a 60" cutting deck. These blades come in a set of three, each approximately 20.5 inches long.
• Model/serial number: Exmark Lazer Z with S/N 540,000 and above. If your serial number is below 540,000, these will not fit.
• OEM number: Direct replacement for Exmark part 103-6403-S. Double-check your current blade’s part number.
• Measurements: Confirm center hole diameter (usually 1" or 5/8") and blade thickness (typically 0.204") to match your spindle. Measure your old blade’s length and hole pattern if unsure.

Key Things to Know

• Quality: Oregon blades are heat-treated and hardened for durability, but they are not as thick as some OEM blades—expect slightly less lifespan under heavy commercial use.
• Installation: Straightforward bolt-on replacement. Use a torque wrench to tighten to 70-90 ft-lbs. Balance blades before installing to reduce vibration.
• Gotcha: These are not universal—they only fit the specific Exmark Lazer Z 60" decks listed. Using on other models or decks may cause poor cutting or damage.
• Storage: Keep blades sharp and store dry to prevent rust. Dull blades tear grass, inviting disease.

Should You Buy It

Buy this set if you own a compatible Exmark Lazer Z 60" deck (S/N 540,000+) and need a cost-effective, reliable aftermarket blade that delivers good cut quality for residential or light commercial use. It’s a solid value at $39.58, but if you mow professionally 40+ hours a week, consider OEM blades for maximum longevity.