Mercedes Sprinter Thermostat Assembly (Unheated) – OEM Wahler | OM642 3.0L | #6422002015

DESCRIPTION:

A failing thermostat is one of those problems that sneaks up on you — your Sprinter either runs too cold and never reaches operating temperature, or the thermostat sticks closed and your temperature gauge climbs into dangerous territory. This is the OEM Wahler unheated thermostat assembly for 2010+ NCV3 Sprinters with the OM642 3.0L V6, complete with housing, opening at 87°C to keep your engine in its optimal thermal range.

What This Part Does

The thermostat acts as the gatekeeper for your engine's cooling circuit. When the engine is cold, it stays closed to allow the engine to warm up quickly. As coolant reaches 87°C, it opens progressively to allow coolant flow through the radiator and maintain a stable operating temperature. A stuck-open thermostat means your engine never fully warms up — hurting fuel economy, oil life, and emissions performance. A stuck-closed thermostat causes rapid overheating.

Unheated vs. Heated — Why It Matters

The OM642 Sprinter uses two thermostat variants — heated and unheated. The unheated version (this part) does not include a port for a temperature sensor. Installing the wrong variant will result in improper fitment or missing sensor connectivity. Always verify which version your engine requires before ordering.

When to Replace It

Replace the thermostat if your Sprinter is overheating, running consistently below normal operating temperature, experiencing erratic temperature gauge readings, or as part of any major cooling system service. This assembly includes the housing and thermostat — no need to source components separately.

Fitment

• 2010–2023 Mercedes-Benz Sprinter 2500 – 3.0L V6 Diesel (OM642)
• 2010–2023 Mercedes-Benz Sprinter 3500 – 3.0L V6 Diesel (OM642)

Note: This part is VIN specific. Due to engine number splits within the OM642 family, always verify your part number against your VIN before ordering. Contact us and we'll confirm fitment before you buy.

Part Numbers

• Mercedes OEM: 6422002015 / A6422002015 / 6422000215
• Manufacturer: Wahler (4490.87D)