The John Deere Z345R mower blade part number found is M170639. The blade set part number found is GY20683. The blade measurement captured is length 21.38 in (543 mm) and center hole 1 in (25 mm). The deck uses 2 blades.
John Deere Z345R Mower Blade Size and Part Numbers
| Mower blade part number | M170639 |
|---|---|
| Mower blade set part number | GY20683 |
| Blade length | 21.38 in (543 mm) |
| Blade center hole size | 1 in (25 mm) |
| Number of blades | 2 blades |
| Blade type | high-lift, mulching, and standard |
Blade Size Comparison Chart
Blade length comparison
John Deere Z345R Blade Notes
| Blade note | The John Deere Z345R blade listing captured here shows single blade part number M170639, blade set part number GY20683, and length 21.38 in (543 mm) and center hole 1 in (25 mm). Use this as a buying guide, then match the blade position, deck size and center-hole style before spending money |
|---|---|
| Deck note | For the John Deere Z345R, the captured deck information is blade count 2 blades. Match the blades to the fitted deck, not just the tractor model name |
| Blade type note | The John Deere Z345R blade style captured here is high-lift, mulching, and standard. Blade type affects airflow and clipping handling, not just cut width |
| Fitment note | For the John Deere Z345R, use the listed specs as a buying guide, but confirm against the operator manual, parts diagram or old blade before ordering |
John Deere Z345R Mower Blade FAQ
What should you check when fitting a 21.38 in (543 mm) blade on the John Deere Z345R?
A 21.38 in (543 mm) blade needs the right center hole, lift style and deck clearance. That is a common lawn tractor blade length range, but it still needs the right center hole, sail/lift shape and deck fitment. Spin the blade by hand after fitting to confirm it clears the deck
Can you modify a John Deere Z345R blade center hole to fit?
Do not do that. The captured center-hole detail is 1 in (25 mm). Grinding or drilling a mower blade can ruin balance and create vibration
Should you buy one John Deere Z345R blade or a full set?
The single blade number captured is M170639, and the set number captured is GY20683. If one blade is bent from damage, one may be fine; if they are worn down, replacing the full set usually gives a cleaner cut
Which blade type should you use on the John Deere Z345R?
The blade type captured is high-lift, mulching, and standard. Use that against the captured fitment value 21.38 in (543 mm). High-lift helps bagging/discharge; mulching blades need the right mulching setup
Mistakes do happen. Blade specs can change by year, mower deck, spindle, serial range and regional parts catalog. Please check the operator manual, old blade stamp, deck tag and official John Deere parts catalog before ordering replacement blades.
