MaxPower 561139B Heavy Duty 3 Blade Set for 60" Cut Exmark, Replaces OEM no. 103-6403, 103-6403-S, 140-1240

What It Is

The MaxPower 561139B is a heavy-duty 3-blade set designed for 60-inch cut Exmark mowers, replacing OEM part numbers 103-6403, 103-6403-S, and 140-1240. It’s built for commercial-grade cutting on large residential or professional turf.

Fitment & Compatibility

Before buying, verify your mower deck is exactly 60 inches—any other size won’t work. This set fits Exmark Lazer Z, Lazer Z X-Series, and Quest models with a 60-inch deck, but cross-check your specific model and serial number against Exmark’s compatibility chart. Measure your existing blades: these are 20.5 inches long, 2.5 inches wide, with a 0.25-inch center hole and a 1-inch center-to-center offset. Ensure your spindle pattern matches (three-hole, 6.5-inch bolt circle). Aftermarket blades like these are direct replacements but may differ slightly in weight or balance versus OEM—test fitment before full use.

Key Things to Know

• Quality: Made from heat-treated alloy steel for durability; holds an edge well but may require sharpening sooner than OEM if used on rough terrain.
• Installation: Easy swap with basic hand tools (wrench and torque wrench). Torque bolts to 70-90 ft-lbs—overtightening can strip spindles.
• Common gotcha: These blades are thicker than some OEM versions (0.25-inch vs. 0.20-inch), which can reduce airflow in high-lift decks. Check for clearance inside your deck to avoid poor discharge.
• Balance: Each blade is individually balanced, but always recheck with a blade balancer after installation to prevent vibration.

Should You Buy It

Buy this set if you have a 60-inch Exmark with the listed OEM numbers and want a cost-effective, heavy-duty alternative that matches OEM quality for most residential and light commercial use. Avoid if you need exact OEM weight for a high-performance cutter deck, or if your mower requires a specific lift profile (e.g., mulching or bagging).