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A Tigercat 880 forestry machine rolling forward on a lowbed during transport is typically caused by insufficient chain restraint or compromised brake pressure. Even with spring-applied brakes, hydraulic release systems can fail under load or leak down over time, making proper chaining the only reliable safeguard.
Tigercat 880 Overview and Brake System Design
Tigercat Industries, founded in 1992 in Ontario, Canada, specializes in forestry equipment engineered for durability and off-road performance. The Tigercat 880 is a purpose-built log loader and processor, often used in mill yards and roadside harvesting. It features a heavy-duty undercarriage, high-capacity swing system, and a cab-forward design for visibility and reach.
The 880’s braking system is independent of the track drive motors. It uses spring-applied, pressure-released wet disc brakes housed outside the track motor, lubricated by planetary gear oil. This configuration provides robust holding power when parked, but depends on hydraulic pressure to release. If pressure bleeds off or the system is not fully charged, the brakes may not engage properly.
Terminology Note
The Tigercat 880 reportedly moved forward on the lowbed after the driver braked at 20 km/h. This suggests that the machine was not adequately restrained, and the internal brake system may have failed to hold due to one or more of the following:
In British Columbia, a contractor transporting a Tigercat 845 noticed the machine shifted slightly on the lowbed during a downhill stop. Investigation revealed that the brake release line had a slow leak, and the planetary oil was below spec. After servicing the brakes and adding a fifth chain, the issue never recurred.
In Georgia, a technician servicing Tigercat 822s noted that brake packs located mid-housing can starve for oil if the final drive level is even slightly low. He recommended topping off planetary oil before every transport and inspecting for leaks around the pressure release fittings.
Conclusion
A Tigercat 880 moving on a lowbed is a serious warning sign of either brake system failure or inadequate chaining. Spring-applied brakes offer protection only when hydraulic pressure is properly managed and oil levels are maintained. For safe transport, mechanical restraint must be the primary defense. Chains, not brakes, keep machines in place when the trailer stops. Always over-chain, inspect brake systems, and treat every load as if it could freewheel.
Tigercat 880 Overview and Brake System Design
Tigercat Industries, founded in 1992 in Ontario, Canada, specializes in forestry equipment engineered for durability and off-road performance. The Tigercat 880 is a purpose-built log loader and processor, often used in mill yards and roadside harvesting. It features a heavy-duty undercarriage, high-capacity swing system, and a cab-forward design for visibility and reach.
The 880’s braking system is independent of the track drive motors. It uses spring-applied, pressure-released wet disc brakes housed outside the track motor, lubricated by planetary gear oil. This configuration provides robust holding power when parked, but depends on hydraulic pressure to release. If pressure bleeds off or the system is not fully charged, the brakes may not engage properly.
Terminology Note
- Spring-Applied Brake: A brake that engages automatically when hydraulic pressure is lost.
- Pressure-Release Line: A hydraulic circuit that disengages the brake when energized.
- Planetary Gear Oil: Lubricant used in the final drive assembly, also serving the brake pack.
- Lowbed: A trailer with a dropped deck used to haul heavy equipment.
- Chain Restraint: The use of steel chains and binders to secure equipment during transport.
The Tigercat 880 reportedly moved forward on the lowbed after the driver braked at 20 km/h. This suggests that the machine was not adequately restrained, and the internal brake system may have failed to hold due to one or more of the following:
- Insufficient chain tension or quantity. Chains must be rated for the machine’s weight and applied in a pattern that prevents forward, backward, and lateral movement.
- Hydraulic pressure loss in the brake release circuit. If the engine is off and the system leaks down, the brakes may not re-engage fully.
- Low planetary oil level, starving the brake pack of lubrication and reducing holding force.
- Brake wear or contamination, especially if the machine operates in muddy or abrasive conditions.
- Always assume the machine can roll. Chain it as if the brakes will fail.
- Use at least four chains, two forward and two rear, with binders rated for the machine’s gross weight.
- Inspect brake function before loading. Engage and disengage the brakes manually to confirm operation.
- Check planetary oil levels. Low oil can compromise brake pack lubrication and wear surfaces.
- Avoid relying solely on hydraulic brakes. Mechanical restraint is essential during transport.
In British Columbia, a contractor transporting a Tigercat 845 noticed the machine shifted slightly on the lowbed during a downhill stop. Investigation revealed that the brake release line had a slow leak, and the planetary oil was below spec. After servicing the brakes and adding a fifth chain, the issue never recurred.
In Georgia, a technician servicing Tigercat 822s noted that brake packs located mid-housing can starve for oil if the final drive level is even slightly low. He recommended topping off planetary oil before every transport and inspecting for leaks around the pressure release fittings.
Conclusion
A Tigercat 880 moving on a lowbed is a serious warning sign of either brake system failure or inadequate chaining. Spring-applied brakes offer protection only when hydraulic pressure is properly managed and oil levels are maintained. For safe transport, mechanical restraint must be the primary defense. Chains, not brakes, keep machines in place when the trailer stops. Always over-chain, inspect brake systems, and treat every load as if it could freewheel.
