John Deere 350B Dozer – Crawler Tractor

Description:

The John Deere 350B Dozer, produced from 1971 to 1975, was the upgraded successor to the original 350 model. It introduced improvements in power, hydraulic response, and overall durability while maintaining the 350's compact, maneuverable frame. With its three-cylinder diesel engine rated at 42–48 HP, the 350B was ideal for clearing, grading, and small-scale earthmoving.

Operators favored its improved 8-speed gear transmission, responsive hydraulic control system, and reinforced undercarriage components. It also offered multiple blade configurations including straight, angle, and six-way (PAT) blades, making it suitable for a wide range of jobs. Like its predecessor, the 350B has stood the test of time thanks to its mechanical simplicity and easy parts access.

Important: Always confirm parts compatibility by referencing the serial number and verifying the machine is a 350B, not a base 350 or later 350C model.

Key Specifications:

The John Deere 350B Dozer is powered by a John Deere 3-cylinder 152 cubic inch diesel engine, delivering between 42 and 48 horsepower, depending on tuning and configuration. It uses a dry clutch and an 8-speed sliding gear transmission with four forward and four reverse gears.

The 350B has an open-center hydraulic system rated around 11 GPM, giving it solid blade responsiveness for its class. Track gauge is approximately 48 inches, with standard 12-inch shoes and 5 bottom rollers per side. Depending on blade setup, the 350B weighs around 10,000 to 10,500 pounds.

Blade options included straight, angle, and six-way (PAT) blades with capacities between 0.9 and 1.1 cubic yards.

Serial Number Information:

Production years and starting serial numbers for the 350B are as follows:

• 1971: 110000

• 1972: 112743

• 1973: 117284

• 1974: 124315

• 1975: 133000 (approximate)

Serial Number Location: Look for the serial number plate on the left side of the machine frame, just behind the track or below the operator platform. On some models, it may also be beneath the seat.

Key Features:

• Improved Powertrain: The 350B retains the gear drive simplicity of the 350 but features smoother shifting and a stronger clutch system.

• Reliable Hydraulic Blade Control: Enhanced open-center hydraulics improve lifting and angle blade responsiveness.

• Compact Footprint, Heavy Build: Ideal for jobs requiring a tough but nimble crawler in tight spaces.

• Multiple Blade Configurations: Choose from straight, angle, or PAT blades depending on task requirements.

• Service-Friendly Design: Easier engine access, modular component layout, and straightforward diagnostics make the 350B easy to maintain.

Common Replacement Parts:

Parts commonly replaced on the JD 350B Dozer include:

• Engine Components: Pistons, head gaskets, water pumps, fuel injectors, and overhaul kits.

• Clutch & Transmission: Dry clutch kits, throwout bearings, pressure plates, and gear synchronizers.

• Undercarriage: Track chains, rollers, sprockets, recoil springs, and adjusters.

• Hydraulics: Lift cylinders, cylinder seal kits, control valves, and hoses.

• Blade & Frame: Cutting edges, blade arms, pins, bushings, and tilt cylinders.

All of these can be found on BrokenTractor.com, including rebuild kits for clutch systems, undercarriage packages, and hydraulic cylinder parts.

Maintenance Schedule:

For peak performance, service the JD 350B as follows:
Change the engine oil and filter every 100 hours. Replace fuel filters every 200 hours and transmission fluid every 250 hours. Inspect the hydraulic system, blade arms, and hoses every 250 hours. Track tension should be checked weekly, especially after heavy use. Flush and inspect the cooling system annually or every 1,000 hours.

Common Issues & Fixes:

• Clutch Slippage: Often due to worn clutch discs or pressure plate. A full clutch rebuild kit can restore functionality.

• Blade Drift or Weak Lift: Caused by worn cylinder seals or low hydraulic pressure. Replace seals or check for pump wear.

• Loose Tracks or Undercarriage Noise: Worn bushings or stretched track links should be addressed with new track chains or adjusters.

• Hard Starting: Check for faulty glow plugs, clogged fuel filters, or injector issues. Full fuel system kits are available.