The deck belt size found is 95 in (2,413 mm) long by 0.5 in (13 mm) wide. The drive belt size found is 134 in (3,404 mm) long by 0.62 in (16 mm) wide.
John Deere M665 Belt Size and Part Numbers
| Mower deck belt length | 95 in (2,413 mm) |
|---|---|
| Mower deck belt width | 0.5 in (13 mm) |
| Drive belt length | 134 in (3,404 mm) |
| Drive belt width | 0.62 in (16 mm) |
Belt Size Comparison Chart
Belt length comparison
Belt width comparison
John Deere M665 Belt Notes
| Mower deck belt note | The John Deere M665 deck belt measurement captured here is length 95 in (2,413 mm) and width 0.5 in (13 mm). Match the old belt, deck size and routing before spending money |
|---|---|
| Drive belt note | The John Deere M665 drive or transmission belt measurement captured here is length 134 in (3,404 mm) and width 0.62 in (16 mm). Do not mix it up with the deck belt because the routing and job are different |
| Fitment note | Before ordering a John Deere M665 belt, compare the old belt routing, pulley layout and deck size if available. A close-looking belt can still be wrong |
John Deere M665 Belt Size FAQ
Why can the correct John Deere M665 deck belt still slip?
The deck belt length found is 95 in (2,413 mm). Even with the right length, a weak idler spring, worn pulley groove or wrong belt path can make it slip. The part number and routing matter together
Why does 0.5 in (13 mm) belt width matter on the John Deere M665?
The captured deck belt width is 0.5 in (13 mm). Pulley grooves are cut for a matching belt profile. Wrong width can cause squeal, heat, poor blade speed or fast belt wear
Are the John Deere M665 deck and drive belt lengths close?
The deck belt is 95 in (2,413 mm) and the drive belt is 134 in (3,404 mm), about 39 in (991 mm) different. That is enough to treat them as separate belts when ordering
Mistakes do happen. Belt specs can change by year, mower deck, pulley layout, serial range and regional parts catalog. Please check the operator manual, belt routing decal, old belt label and official John Deere parts catalog before ordering a replacement belt.
