Forklift Torque converter

Forklift Torque Converter: Hydraulic Coupling for Powershift Transmissions

The forklift torque converter transfers and multiplies engine torque to the transmission through hydraulic fluid coupling — eliminating the mechanical clutch entirely. When a converter fails, the forklift loses pulling power under load, transmission fluid overheats and burns, and metal debris from the disintegrating stator or impeller contaminates the entire hydraulic system. Kingstream supplies OEM-spec torque converters for Clark CQ20D-CQ30D, Doosan D50S-D70S, Komatsu C12/C14, Tailift 4105-4108, TCM 3T, and FD50-100 series forklifts, with every unit inspected for hub runout, stator sprag clutch function, and weld integrity before shipment.

When to Replace Your Torque Converter — Common Symptoms
• Engine RPM rises but forklift accelerates slowly or cannot climb ramps → Stator one-way clutch has failed, eliminating torque multiplication
• Transmission fluid smells burnt and appears dark on dipstick → Excessive internal slippage converting engine power to heat instead of motion
• Metallic rattling or grinding from bellhousing that changes with RPM → Damaged impeller blades or failed stator sprag clutch
• Shudder during acceleration from standstill, especially with a load → Glazed lockup clutch friction material
• Metal particles found in transmission fluid or filter → Catastrophic internal failure; requires complete transmission flush and valve body cleaning

OEM Cross-Reference / Available Models

Don’t see your model? Send us your engine and transmission model →

Compatible Forklift Brands
Doosan D50S/D60S/D70S, Clark CQ20D/CQ25D/CQ30D, Komatsu C12/C14, Liugong CLG856/LG956/ZL50G, Tailift 4105-4108 (YJH3.15H), TCM 3T, FD50-100 (15943-80211)

Browse our complete Forklift Hydraulic Transmission Parts catalog for input plates, clutch packs, and transmission filters.