Wholesale High Quality Booster Pump Auto Parts Oem 854-05109 Brake Booster For Isuzu 4hf1

Brake Vacuum Booster for Isuzu 4HF1 — OEM 854-05109 Compatible

This brake vacuum booster is a direct OEM-compatible replacement for the Isuzu 4HF1 diesel engine platform used in industrial forklifts and construction equipment, matching OEM part number 854-05109 specifications. Designed for 5-10 ton internal combustion forklifts equipped with vacuum-assisted hydraulic drum brake systems, this booster amplifies mechanical pedal force using engine intake manifold vacuum to deliver consistent, fatigue-free braking performance during extended shift operations in demanding industrial environments.

The booster features a heavy-gauge stamped steel housing with corrosion-resistant electrocoat finish and a reinforced single-diaphragm design that provides approximately 4-6 times pedal force multiplication. The internal reaction disc is calibrated for progressive brake feel — light initial effort for gentle low-speed deceleration, with proportionally increased assist as pedal force rises during heavy-load or emergency braking. The one-way check valve on the vacuum port maintains vacuum reserve for power-assisted stops even after engine shutdown. Mounting studs, push rod length, and vacuum line fitting match Isuzu OEM dimensions for direct bolt-on installation.

Application includes Isuzu 4HF1-powered forklifts in the 5-10 ton class, including select HELI, Hangcha, Lonking, and other domestic models using the Isuzu 4HF1 engine platform with vacuum brake systems. Verify the firewall mounting stud pattern and push rod length before installation. Replace the vacuum hose and check valve during booster replacement. For compatible Isuzu engine parts and complete brake overhaul kits, visit our Forklift Brake Parts section.

Technical Specifications

• SKU: BOOSTER-4HF1-854
• OEM Reference: 854-05109 Compatible
• Engine: Isuzu 4HF1 Diesel
• Capacity: 5-10 Ton Forklift
• Housing: Steel, Electrocoat Finish
• Includes: Booster, Check Valve, Gasket

Compatible Equipment

Each booster is vacuum-tested and pressure-checked before packaging. Ships with check valve installed. 12-month warranty. Contact our team.