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8-Rib Fan Belt for John Deere 850J Dozer & 644/724J Loader

SKU:
R133703
FitsModel:
850J-II, 644H, 644J, 724J, 5083E, 5093E, 5101E, 5425, 5525, 5603, 5625, 5725
ListDescription:
Fan Belt (75.85" Long)
John Deere 850J-II dozer 644J 724J loader fan drive belt R133703
Part # R133703

Fits Models At A Glance:

  • John Deere Dozers: 850J-II
  • John Deere Wheel Loaders: 644H, 644J, 724J
  • John Deere 5000 Series Tractors: 5083E, 5083EN, 5093E, 5093E Limited, 5093EN, 5101E, 5101EN, 5425, 5425H, 5425HC, 5425N, 5525, 5525N, 5603, 5625, 5625HC, 5725, 5725H, 5725HC

Key Notes:

  • Part Numbers: R133703, T428703
  • Also Known As: AR133703, AAR133703, AMR135823, A751K8
  • Metric Code: 8PK1907
  • Weight: 0.67 lbs (0.30 kg)
  • Type: K Micro Rib (Poly-V / Serpentine) belt
  • Material: Polyester cord construction
  • Color: Black
  • Pitch Length: 75.1"
  • Outside Length: 75.85"
  • Width: 8 Rib
  • Thickness: 0.18"
  • Application: Engine fan drive belt — drives the engine cooling fan and accessory drive system on John Deere 850J-II dozers, 644/724 series wheel loaders, and 5000 series utility tractors
  • Condition: Aftermarket replacement part

⚠️ Important — Configuration & Serial Number Notes for 5000 Series Tractors: Confirm cab, serial number, and configuration before ordering:

  • 5083E, 5093E Limited, 5101E — Fan Drive With Cab, Serial Number 339999 and below
  • 5083EN, 5093EN, 5101EN — Fan Drive With Cab, Serial Number 369999 and below
  • 5425N — Fan Drive With Cab, Straddle Mount configuration only
  • 5425, 5425H, 5425HC, 5625, 5625HC, 5725H — Orchard configuration only
  • 5525 — With Cab only
  • 5603, 5725 — Fan Drive With Cab, 1907.5mm wheelbase

Common Use Case or Symptoms: Use when the fan drive belt is cracking, glazing, squealing, or has broken — a worn or failed fan belt will cause engine overheating across all applicable John Deere dozer, wheel loader, and 5000 series tractor models.

Why Choose Broken Tractor:

  • ✅ Cross-Platform Coverage: One belt number covers John Deere's 850J-II dozer, 644/724 series wheel loaders, and multiple 5000 series utility tractor configurations
  • ✅ 8-Rib K Micro Rib Design: Multi-rib serpentine belt construction provides superior grip, reduced slip, and efficient fan drive power transfer
  • ✅ Fast Shipping from a U.S.-Based Team: In-stock and ready to ship same day from our U.S. warehouses
$28.00

Shipping charges are calculated at checkout.
Items are NOT guaranteed to be in stock at the time of order.
Refunds are offered if the item is on back-order.

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Product: Category: Brand: Head Title: Engine Fan Drive Belt | Broken Tractor | R133703