8TEN LawnRAZOR Mulching Blades for John Deere 42" Deck (M170642) — 2-Pack, Balanced Steel

If your mower is leaving uneven clippings, struggling with mulching, or the deck is working harder than it should, these replacement blades are built to bring back a clean, efficient cut. Designed to match the mounting pattern and dimensions of John Deere M170642 OEM parts, the 8TEN LawnRAZOR blades deliver mulching-style airflow, consistent blade tip speed, and durable steel construction so you can maintain a tidy lawn without unnecessary vibration or damage to the deck.

How will these blades change the way my mower cuts?

These blades are shaped for mulching, which chops grass into finer pieces and recirculates clippings under the deck. That improves decomposition on the lawn and reduces the need to bag every mow. Expect a more uniform discharge pattern, fewer clump formations, and reduced scalping when installed correctly.

• Mulch-rolled blade profile for finer clipping circulation
• Balanced design to minimize vibration and wear
• Edges ground to restore sharp tip speed and cutting efficiency

Which John Deere models and deck sizes are these compatible with?

These 8TEN blades are made to be directly compatible with John Deere OEM part M170642 and fit several common lawn tractor and ZTrak models that use a 42" cutting deck. Check your mower manual or compare blade hole pattern and dimensions before purchase to ensure fitment.

• Fits John Deere X330, X350, X354, X370, X380 models
• Also fits Z335E, Z335M, Z345M, Z345R models using a 42" deck
• Designed specifically for 42-inch deck mounting and spacing

What are the exact dimensions and mounting details?

Knowing the precise blade measurements helps confirm compatibility and balance in your deck. These blades follow the common aftermarket dimensions that match the OEM hole pattern and thickness typical for John Deere 42" mulching blades.

• Overall length: 21 3/8" (21.375")
• Cutting width: 2 3/4" (2.756") and thickness 0.197"
• Center hole circle diameter: 13/16" (0.803") — rolled mulching type

How do I install and maintain these replacement blades?

Installation follows standard mower blade replacement steps: raise and secure the mower, remove deck or support it, unbolt old blades, and install new blades with the correct orientation and torque. Keep blades sharp and balanced, check fasteners after the first use, and inspect for damage regularly to prolong blade and deck life.

• Torque mounting bolts to your tractor manufacturer’s specification
• Sharpen and balance blades periodically for best mulching action
• Replace blades in matched pairs to maintain balance on a 42" deck

Who this is for: The 8TEN LawnRAZOR 2-pack is aimed at homeowners and property caretakers who own John Deere tractors or ZTrak mowers with a 42" deck and want OEM-equivalent mulching performance without the OEM price tag. It’s appropriate for users who prefer mulching to bagging, need to replace worn or damaged blades, or want to upgrade to a matched pair for smoother, more consistent cutting across the deck.