John Deere 550B Dozer – Crawler Tractor (Second-Gen 550 Series)

The John Deere 550B Dozer, built from the late 1970s through the mid-1980s, is the second-generation version of the 550 crawler, offering improved durability, stronger blade hydraulics, and better service access. It’s powered by a naturally aspirated 4-cylinder diesel engine delivering ~70 HP, with a simple 8-speed manual transmission and open-center hydraulics, making it a dependable, easy-to-maintain dozer for grading, clearing, and slope work.

Key Specifications:

• Engine:
  John Deere 4239D, 4-cylinder, 239 cu in naturally aspirated diesel

• Horsepower:
  ~70 HP

• Transmission:
  8-speed gear drive (4 forward, 4 reverse)

• Hydraulics:
  Open center, approx. 13–14 GPM

• Operating Weight:
  ~14,500 – 15,500 lbs

• Blade Type:
  Straight, Angle, or 6-Way PAT

• Blade Capacity:
  ~1.3 cubic yards

• Undercarriage:
  5 bottom rollers per side, SALT track optional

Serial Number Information:

• Production Years: ~1979–1986

• Serial Number Location:
  Left side of the machine frame, near the operator’s platform or front track support. Always confirm the serial number before ordering parts.

Key Features:

• ✅ Reliable 4239D Engine:
  Known for fuel efficiency, longevity, and easy rebuilds.

• ✅ Manual 8-Speed Transmission:
  Fully mechanical, simple to service, and parts are readily available.

• ✅ Durable Blade System:
  Compatible with straight, angle, and 6-way configurations for varied jobsite needs.

• ✅ Open-Center Hydraulics:
  Smooth and responsive blade movement with straightforward maintenance.

• ✅ Heavy-Duty Undercarriage:
  Designed to handle tough terrain with minimal downtime.

Common Replacement Parts:

Available at Broken Tractor

• Engine Parts: Pistons, sleeves, gaskets, fuel injectors, water pumps

• Transmission & Clutch: Clutch kits, pressure plates, throwout bearings, gears

• Hydraulics: Blade lift cylinders, hoses, seal kits, control valves

• Undercarriage: Track chains, rollers, sprockets, idlers, recoil springs

• Blade Hardware: Pins, bushings, cutting edges, tilt cylinders

Maintenance Schedule:

• Engine Oil & Filter: Every 100 hours

• Fuel Filters: Every 200 hours

• Transmission Fluid: Every 250 hours

• Hydraulic System Service: Every 250 hours

• Cooling System Flush: Every 1,000 hours

• Grease Track & Blade Points: Weekly or after heavy use

Common Issues & Solutions:

• Blade Drops or Lags:
  Worn seals or hoses — fix with hydraulic cylinder kits

• Stiff Steering or Poor Turn:
  May indicate worn clutch or linkage — install steering clutch kits

• Track Slack or Wear:
  Common in older machines — rebuild with undercarriage parts

• Low Power or Fuel Issues:
  Replace worn injectors or clean fuel system — engine kits available