The Murray X31B lawn tractor uses three published belt sizes: 1/2" Wide x 86" O.D. for the engine to deck belt / primary cutter deck belt, 1/2" Wide x 53 11/16" O.D. for the cutter deck belt, and 1/2" Wide x 30 3/16" O.D. for the transmission / motion drive belt. Match each belt to its correct position and OEM reference before ordering.
Belt replacement guide
Murray X31B belt size & replacement chart
OEM references, belt positions and published dimensions for this lawn tractor.
Match the belt function first, then confirm the OEM number and size.
Belt application
OEM / replacement number
Published size
Listing SKU
Mower deck Engine to Deck Belt / Primary Cutter Deck Belt
37X89, 037X89, 037X89MA, 710217, 7101748YP
1/2" Wide x 86" O.D.
BEL37X89
Mower deck Cutter Deck Belt
37X57, 037X57, 037X57MA
1/2" Wide x 53 11/16" O.D.
BEL37X57
Transmission / motion Transmission / Motion Drive Belt
37X65, 037X65, 037X65MA
1/2" Wide x 30 3/16" O.D.
BEL37X65
Application details
Which Murray X31B belt do you need?
Engine to Deck Belt / Primary Cutter Deck Belt
Recorded OEM references: 37X89, 037X89, 037X89MA, 710217, 7101748YP. Published size: 1/2" Wide x 86" O.D.
Cutter Deck Belt
Recorded OEM references: 37X57, 037X57, 037X57MA. Published size: 1/2" Wide x 53 11/16" O.D.
Transmission / Motion Drive Belt
Recorded OEM references: 37X65, 037X65, 037X65MA. Published size: 1/2" Wide x 30 3/16" O.D.
Important: Confirm the belt position, deck size, serial range and machine configuration before ordering. Belts with the same length can use different widths or profiles.
Common questions
Murray X31B belt FAQ
What belt does the Murray X31B use?
The listed belt applications are Engine to Deck Belt / Primary Cutter Deck Belt, Cutter Deck Belt, and Transmission / Motion Drive Belt. Recorded OEM references: 37X89, 037X89, 037X89MA, 710217, 7101748YP, 37X57, 037X57, 037X57MA, 37X65, 037X65, and 037X65MA.
What are the Murray X31B belt part numbers?
The recorded OEM references are 37X89, 037X89, 037X89MA, 710217, 7101748YP, 37X57, 037X57, 037X57MA, 37X65, 037X65, and 037X65MA. Match each number to the correct belt position before ordering.
What belt sizes does the Murray X31B use?
Engine to Deck Belt / Primary Cutter Deck Belt: 1/2" Wide x 86" O.D., Cutter Deck Belt: 1/2" Wide x 53 11/16" O.D., and Transmission / Motion Drive Belt: 1/2" Wide x 30 3/16" O.D.
Why are multiple belts listed for the Murray X31B?
This machine has 3 recorded belt applications. Different belts can operate the mower deck, transmission, PTO, clutch or other drive components.
Can I match the Murray X31B belt by length alone?
No. Width, profile, inside or outside circumference, belt position and OEM reference can all affect fitment. Match the belt function and OEM number first, then use the dimensions as a final check.
