Toro 4PK Genuine OEM TimeCutter 42" Deck Lawn Mower Blades 131-3939-03

What It Is

This is a set of four genuine OEM Toro replacement blades designed specifically for 42-inch TimeCutter zero-turn mowers. They cut grass with a standard low-lift profile, making them ideal for residential mowing on flat to moderate terrain.

Fitment & Compatibility

Before buying, confirm your mower has a 42-inch cutting deck and is a Toro TimeCutter model (e.g., SS4225, Z4200, ZS4200). These blades are not universal—they won’t fit other brands or deck sizes. Each blade measures 21.75 inches long with a 1-inch center hole and 0.25-inch thickness. Check your current blade’s part number (likely 131-3939-03) to ensure a match. OEM blades guarantee proper balance and mounting, while aftermarket alternatives may require modification.

Key Things to Buy

• OEM quality – Genuine Toro blades are heat-treated and precision-balanced for longer life and less vibration vs. generic options.
• Installation difficulty – Moderate. You’ll need a socket wrench and a blade removal tool (or a block of wood to jam the blade). Torque to 70–90 ft-lbs.
• Common gotchas – Always replace all four blades at once to maintain even cutting. Check the deck for spindle wear or debris buildup before installing. Use thread-locker on bolts to prevent loosening.
• Performance – These are low-lift blades, so they’re poor for mulching or bagging heavy wet grass. For that, consider Toro’s high-lift or mulching blade kits.

Should You Buy It

Buy these if you own a 42-inch Toro TimeCutter and want a direct, hassle-free replacement that maintains factory cutting quality and deck balance. Skip them if you need mulching or bagging performance, or if you’re willing to gamble on cheaper aftermarket blades that may require balancing or fitment tweaks.