Mower Blades M170639 / GY20683 / UC22008 for John Deere 42-Inch Deck

Overview

This aftermarket 2-Pack, 4-Pack, 6-Pack standard mower blade listing replaces common blade numbers including M170639 / GY20683 / UC22008 used on select John Deere mower deck applications.

Available package options are 2-Pack, 4-Pack, 6-Pack. Select the quantity that matches your deck blade count or the number of full blade changes you want on hand. Always match your original blade number, blade length, center-hole style, deck size, blade count, and mower model before ordering.

Key Features

• Aftermarket mower blade set for select mower deck applications
• Package options: 2-Pack, 4-Pack, 6-Pack
• Replacement path: M170639 / GY20683 / UC22008
• Blade style: Standard

Compatible Brands & Model Series

This blade set is used on select John Deere mower deck applications with 42 inch decks.

Source fitment examples:

• John Deere: S220 200 Series Tractor
• John Deere: S240 Sport Lawn Tractor
• John Deere: X330, X350, X354, X370 Lawn and Garden Tractor
• John Deere: Z315E, Z320M, Z320R, Z335E, Z335M, Z345R ZTrak Mower

Fitment note: Match your original blade number and confirm that your deck uses the selected package quantity with the correct mounting pattern.

Replaces OEM Part Numbers

• M170639
• GY20683
• UC22008

Blade Specifications

• Blade length: 21-3/8 inch
• Blade width: 2.99 inch
• Blade thickness: 0.16 inch
• Center hole: 0.79 inch
• Common deck size: 42 inch
• Blade type: Standard

Quick Ship Fulfillment

This item may ship directly from one of our trusted U.S. distribution partners to help reduce transit time. Packaging, labeling, or warehouse origin may vary, but the part will match the replacement numbers, fitment notes, and specifications shown in this listing.

Why Buy From PTO Direct USA

• Focused replacement parts for mower deck and PTO repair
• Part-number-first listings to help reduce fitment mistakes
• Clear replacement numbers and fitment notes before you order
• Fast, practical support if you need help checking compatibility

Need Help Confirming Fitment?

If you are not sure whether this blade set fits your mower, send us your mower model number, deck size, and the part numbers from your original blades. We can help you compare them before you order.

FAQ

Will this fit all 42 inch decks?

No. This blade set fits select applications only. Match your original blade number, blade length, center-hole style, deck layout, and mower model before ordering.

Which package quantity should I choose?

For 2-blade decks, select the 2-Pack for one complete blade change; 4-Pack and 8-Pack options cover multiple services. For 3-blade decks, select the 3-Pack for one complete blade change or the 6-Pack for two complete blade changes.

What should I check before installing?

Compare blade length, center-hole pattern, lift style, deck layout, and original blade number against your mower or OEM diagram. Stop installation if the blades do not match your original setup.