Rotary Set of 3 11479 17.9" Blades

What It Is

This is a set of three 17.9-inch replacement blades from Rotary, designed for medium-duty residential mowing on 54-inch or similar three-blade lawn tractor decks. They are intended for standard grass cutting, not mulching or bagging specialized use.

Fitment & Compatibility

Before buying, verify these three fitment factors:

• Deck size: These are 17.9" long, so they fit decks that accept blades between 17.5" and 18.0". Measure your existing blade length—do not rely on deck size alone.
• Center hole & drive: Check that the center hole diameter (usually 1" or 7/8") and drive pin pattern match your spindle. Rotary blades often use a standard 5-point star or oval hole; measure yours.
• OEM cross-reference: This set is aftermarket. Common OEM replacements include John Deere (e.g., AM141032, AM137340) and Husqvarna (e.g., 53211479). Cross-check your mower brand/model with the OEM part number—don’t assume universal fit.
• Lift & thickness: These are standard lift blades, typically 0.1875" thick. If your mower requires high-lift or mulching blades, these won’t perform correctly.

Key Things to Know

• Quality: Decent for the price, but aftermarket steel may dull faster than OEM. Expect 1-2 seasons of regular mowing before replacement.
• Installation: Straightforward if you have a socket and torque wrench (tighten to 70-90 ft-lbs). Use thread locker if recommended by your mower manual.
• Common gotcha: The blade set includes three identical blades, but some mowers use staggered lengths (e.g., one shorter). Measure all three old blades before buying.
• Balance: Aftermarket blades can be slightly out of balance. Check with a blade balancer and file the heavy side if needed—unbalanced blades cause vibration and spindle wear.

Should You Buy It

This set is a solid budget option if you need three standard 17.9-inch blades for a residential tractor and have verified compatibility with your deck spindle pattern. It’s not for commercial use or specialized cutting needs—skip it if you require high-lift or mulching blades, or if your mower uses non-standard lengths. For the price, it’s a practical replacement for basic weekly mowing.