The John Deere 445 deck belt part number found is M120381. The deck belt size found is 124.6 in (3,165 mm) long by 0.5 in (13 mm) wide. The drive belt part number found is M120381. The drive belt length found is 98.1 in (2,492 mm).
John Deere 445 Belt Size and Part Numbers
| Mower deck belt part number | M120381 |
|---|---|
| Mower deck belt length | 124.6 in (3,165 mm) |
| Mower deck belt width | 0.5 in (13 mm) |
| Drive belt part number | M120381 |
| Drive belt length | 98.1 in (2,492 mm) |
Belt Size Comparison Chart
Belt length comparison
Belt width comparison
John Deere 445 Belt Notes
| Mower deck belt note | The John Deere 445 deck belt listing shows part number M120381, length 124.6 in (3,165 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 445 drive or transmission belt listing shows part number M120381 with length 98.1 in (2,492 mm). Do not mix it up with the deck belt because the routing and job are different |
| Fitment note | The blunt rule with the John Deere 445: part number beats guesswork. If the belt is off by even a small amount, it can slip, squeal, jump pulleys or wear fast |
John Deere 445 Belt Size FAQ
What should you watch when fitting a 124.6 in (3,165 mm) deck belt on the John Deere 445?
A 124.6 in (3,165 mm) deck belt leaves little room for sloppy routing. This is a longer mower belt run, so twist, idler alignment and the belt keeper positions matter. A belt can be the right length and still fail if it is routed wrong. Before blaming the new belt, compare the belt path to the routing decal and make sure it sits on the correct side of.
Why does 0.5 in (13 mm) belt width matter on the John Deere 445?
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 445 deck and drive belt lengths close?
The deck belt is 124.6 in (3,165 mm) and the drive belt is 98.1 in (2,492 mm), about 26.5 in (673 mm) different. That is enough to treat them as separate belts when ordering
Is the captured John Deere 445 drive belt part number enough to buy from?
The captured drive belt number is M120381. That is useful for OEM lookup, but the drive belt width was not fully captured here. It is weak data for guessing an aftermarket belt by size alone
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.
