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SKU:
NLT1B01285
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John Deere 48/54-Inch Mower Deck Springs M134312 2-Pack
$35.99
In Stock
$35.99
Sale price
$35.99
Regular price
This new aftermarket two-pack of deck extension springs replaces John Deere M134312 for compatible 48- and 54-inch mower decks and selected 60-inch applications using the same secondary-drive spring.
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
- John Deere 180, 240, 245, 260, 265, 285, 320, 325, 335 and 345
- John Deere GT242, GT262 and GT275
- John Deere GX325, GX335, GX345 and GX355
- John Deere LX172, LX173, LX176, LX178, LX186 and LX188
- Sabre 1842GV, 1842HV, 1848GV, 1848HV, 1948GV, 1948HV, 2048HV, 2148HV, 2254HV, 2354HV and 2554HV
- Scotts S2048, S2348 and S2554
- John Deere G100 and compatible 48-, 54-, or listed 60-inch decks using M134312
Product Overview
A deck belt that slips, jumps a pulley, or stays loose after correct routing may be missing a spring or may have one that has stretched, rusted, or lost tension. Worn idlers, damaged brackets, incorrect belt length, and seized spindles should be checked at the same time.
The extension spring loads the matching secondary idler mechanism so the mower belt stays engaged around the deck pulleys. It is not a universal spring, and installing a shorter or stronger substitute can overload bearings or create a safety hazard.
Match M134312, free length, hook direction, wire diameter, spring location, mower deck size, deck serial tag, and parts diagram. Similar tractor models can carry more than one deck configuration.
Key Features & Performance
- Two replacement extension springs in the package
- Secondary mower-deck drive application
- Original reference and hook shape provide clear comparison points
- Helps return proper idler loading when the old springs are weak
Replaces Part Numbers
- M134312
Common Uses
- Replacing paired springs during deck rebuild work
- Correcting a loose deck belt after routing and pulley checks
- Replacing a rusted or broken spring before mowing season
Technical Specifications
- Product Type: Mower-deck extension spring set
- Quantity: Two springs
- Deck Application: Select 48-, 54- and 60-inch decks
- Condition: New aftermarket replacements
Installation & Fitment
- Remove the key and disconnect the spark-plug leads or battery
- Lower and secure the mower deck
- Use a spring puller and keep hands clear of stored tension
- Inspect idlers, spindle bearings, belt, and spring anchor holes
- Confirm belt routing and guard installation before operating
Compatibility Notice
Northline Parts does its best to list all known compatible models, but the correct part may fit an application that is not shown above. Model year, production date, serial number, engine or equipment specification, installed options, and previous repairs can change fitment. Match the original part, reference number, dimensions, connectors, mounting points, and product photos before purchase.
Frequently Asked Questions
Q: Can these springs fix a belt that keeps coming off? A: They may if the originals are weak or broken, but pulley alignment, bearings, belt size, and routing also matter.
Q: Will they fit every 54-inch Deere deck? A: No. Match the deck parts diagram and M134312 rather than deck width alone.
Q: Why are two springs included? A: The package contains two matching replacement springs for service needs; install only where the deck diagram calls for them.
Q: Is this an original-equipment part? A: No. This is a new aftermarket product. Brand names and part numbers are used only to identify compatible applications.
Part Summary
keywords: John Deere M134312 deck spring, 48 inch mower belt tension spring, 54 inch Deere deck spring 2 pack, GX345 secondary drive spring, Sabre mower belt keeps slipping
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, specifications, and application before purchase.