D552405 THERMOSTAT AS for Doosan B15/18/20T5 Forklifts
Overview
The D552405 THERMOSTAT AS is a Doosan replacement part for the manufacturer’s compact electric counterbalance forklift ranges. This complete thermostat assembly regulates coolant flow through the truck’s cooling circuit, keeping the drive system at its designed operating temperature. When a thermostat sticks open or closed, operators typically notice sluggish performance, warning faults or overheating under load. Fitting the correct D552405 assembly restores accurate temperature regulation and helps protect the motor, electronics and coolant system from heat-related wear, keeping your truck productive shift after shift.
Compatibility
This thermostat fits a broad family of Doosan electric forklifts. The D552405 for B13/15/18/20T-2(SB1025) trucks is also the correct reference across these related series:
- B13/15/18/20T-2 and B13/15/18/20T2 series (SB1025, SB1041)
- B15/18/20T5 series (SB1066), including the 48V AC/SE motor configuration
- B15/18S2 series (SB1030)
- B16/18/20X and B16/18/20X5 series (SB1022, SB1067)
Before ordering, match the number D552405 against the marking on your existing unit or the listing in your truck’s parts manual. If you are not certain which thermostat your serial number requires, our team can verify compatibility before you order.
Quality and Reliability
Because this assembly is manufactured to Doosan’s own engineering specification, it delivers the exact fit, flow characteristics and temperature response the original part was designed around. The housing, sensing element and valve are dimensioned to drop straight into the factory position, so no modification is required. Choosing a specification-correct thermostat instead of an unverified substitute helps maintain consistent operating temperatures across long duty cycles, supporting dependable performance on trucks such as the B16/18/20X and B15/18/20T5 series.
Installation and Maintenance Tips
- Allow the cooling system to cool fully and release residual pressure before opening the circuit.
- Drain coolant to below the thermostat housing level and capture it for inspection.
- Note the orientation of the original thermostat before removal; correct flow direction is essential.
- Clean the housing mating faces and fit new seals or gaskets to prevent leaks.
- Refill with the coolant grade specified by Doosan, bleed the circuit and check for leaks after the first run.
Inspecting coolant condition at scheduled service intervals also helps extend the working life of your new thermostat assembly.
Why Order from Us
At forkliftpartssearch.com we specialise in replacement parts for Doosan forklifts, from fast-moving wear items to assemblies like the D552405 THERMOSTAT AS. Our catalogue is organised by part number and model series, so identifying the right component for a B15/18/20T5 or B16/18/20X5 truck takes minutes rather than hours. Every enquiry is handled by a team that understands forklift downtime, and we are glad to confirm compatibility against your model and serial number before you commit to an order. For dependable Doosan parts support and a straightforward buying experience, order your D552405 thermostat assembly from forkliftpartssearch.com today.