The John Deere GX255 mower blade part numbers found are GX255 and GX21785. The blade set part numbers found are UC20448 and GX255. The blade measurement captured is length 17 in (432 mm) and center hole 0.62 in (16 mm). The deck uses 3 blades.
John Deere GX255 Mower Blade Size and Part Numbers
| Mower blade part number | GX255 and GX21785 |
|---|---|
| Mower blade set part number | UC20448 and GX255 |
| Blade length | 17 in (432 mm) |
| Blade center hole size | 0.62 in (16 mm) |
| Number of blades | 3 blades |
| Blade type | high-lift, mulching, bagging, and 3-in-1 |
Blade Size Comparison Chart
Blade length comparison
John Deere GX255 Blade Notes
| Blade note | The John Deere GX255 blade listing captured here shows single blade part numbers GX255 and GX21785, blade set part numbers UC20448 and GX255, and length 17 in (432 mm) and center hole 0.62 in (16 mm). Do not buy purely from model name if the mower deck or serial range is different |
|---|---|
| Deck note | For the John Deere GX255, the captured deck information is blade count 3 blades. Deck size matters because the same model family can use different blade kits |
| Blade type note | For the John Deere GX255, blade type is listed as high-lift, mulching, bagging, and 3-in-1. Pick the blade style for the job: clean discharge, bagging lift, or mulching |
| Fitment note | Before ordering John Deere GX255 blades, compare the old blade stamp, center-hole shape, blade length and deck size. Close-looking blades can still be wrong |
John Deere GX255 Mower Blade FAQ
Why can the right-length John Deere GX255 blade still be wrong?
The blade length found is 17 in (432 mm), but length alone does not confirm fitment. Center-hole shape, blade offset, sail height and deck size can all change fit
Can you modify a John Deere GX255 blade center hole to fit?
Do not do that. The captured center-hole detail is 0.62 in (16 mm). Grinding or drilling a mower blade can ruin balance and create vibration
What is the difference between the John Deere GX255 blade number and blade set number?
The captured single blade number is GX255 and GX21785, while the captured blade set number is UC20448 and GX255. Use the single blade number for one replacement and the set number when replacing the full deck set
Can you swap John Deere GX255 blade types?
The blade type captured is high-lift, mulching, bagging, and 3-in-1. You can often choose a different style only if it fits the same deck and spindle setup. Use 17 in (432 mm) as the fitment starting point
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.

