Genuine OEM 2782000815 - Engine Coolant Thermostat Kit

Product Overview

The Genuine OEM 2782000815 engine coolant thermostat kit maintains optimal engine operating temperature across Mercedes-Benz V8-powered models from 2011 to 2020. This factory-spec component fits the S-Class (W221 and W222), CL-Class (C216), CLS-Class (C218), E-Class (W212), ML-Class (W166), GL-Class (X166), GLS-Class (X167), and SL-Class (R231) sedans, coupes, and roadsters equipped with 4.7L and 5.5L V8 engines. As a Genuine OEM part, it meets Mercedes-Benz factory specifications and is the choice for dealership service and warranty-backed repairs.

Note: Thermostats are typically replaced as a complete kit. Order this single kit per engine service interval or diagnostic replacement.

Symptoms of a Failing Engine Coolant Thermostat

• Engine running hotter than normal; temperature gauge climbing into the warning zone
• Coolant leaks from the thermostat housing or surrounding connections
• Inconsistent cabin heating; heater blows cold air initially, then hot
• Engine overheating during city driving or idle conditions
• Check Engine Light or coolant temperature warning illuminated on the instrument cluster
• Reduced fuel economy due to engine running outside optimal temperature range

Cross Reference Numbers

This Genuine OEM 2782000815 is equivalent to or replaces the following part numbers: 278200815.

Vehicle Compatibility

This part fits the popular models below. For Fitment Confidence, please use the vehicle selector tool above to verify exact compatibility for your vehicle.

• Mercedes-Benz S550 4.7L V8 Gas (W222): 2012–2016
• Mercedes-Benz S550 4.7L V8 Gas RWD (W221): 2011–2012
• Mercedes-Benz S63 AMG 5.5L V8 Gas (W222): 2012–2013
• Mercedes-Benz S63 AMG 5.5L V8 Gas (W221): 2011
• Mercedes-Benz CL550 4.7L V8 Gas (C216): 2011–2014
• Mercedes-Benz CL63 AMG 5.5L V8 Gas (C216): 2011–2012
• Mercedes-Benz CLS550 4.7L V8 Gas (C218): 2012–2017
• Mercedes-Benz CLS63 AMG 5.5L V8 Gas (C218): 2012
• Mercedes-Benz E550 4.7L V8 Gas (W212): 2012–2016
• Mercedes-Benz E63 AMG 5.5L V8 Gas (W212): 2012
• Mercedes-Benz ML550 4.7L V8 Gas (W166): 2012–2014
• Mercedes-Benz GL450 4.7L V8 Gas (X166): 2013–2014
• Mercedes-Benz GL550 4.7L V8 Gas (X166): 2013–2016
• Mercedes-Benz GLS550 4.7L V8 Gas (X167): 2017–2019
• Mercedes-Benz SL550 4.7L V8 Gas (R231): 2013–2020

This may also fit other applications. Please use the vehicle selector tool to verify fitment.

Often Replaced Together

For a complete cooling system service, many owners replace the following at the same time:

• Engine coolant (OEM Mercedes-Benz specification; typically 1 to 2 gallons depending on capacity)
• Coolant hoses and clamps (inspection recommended; replacement if cracked or softened)
• Water pump (preventive replacement on higher-mileage engines)
• Radiator or radiator cap (if leaking or pressure-test failure)

Why Shop at eEuroparts.com?

• Proven Expertise: Over 25 years of experience with European vehicles means we know your car inside and out.
• Fitment Confidence: Our accurate cataloging ensures you get the right part the first time, backed by our fitment guarantee.
• Fast, Reliable Shipping: Most in-stock orders ship the same or next business day from our U.S.-based warehouse.
• Transparent Pricing: Competitive prices with no hidden fees or surprise charges.
• Exclusive Kits That Fit™: Complete repair solutions with no guesswork.
• Established Trust: Serving the European car community since 2000.

Frequently Asked Questions

How do I know if my Mercedes-Benz S550, CL550, or E550 needs a new thermostat?

Common signs include the engine running hotter than normal, inconsistent cabin heating, coolant leaks around the thermostat housing, or a coolant temperature warning on the instrument cluster. A professional diagnostic scan can confirm thermostat malfunction by monitoring coolant temperature behavior during engine warm-up and load conditions.

What is a thermostat kit and why is it better than a single thermostat?

A thermostat kit includes the thermostat housing, gaskets, seals, and related components pre-matched for proper fit and function. Kits reduce the risk of incomplete repairs or mismatched parts that can cause leaks or poor temperature regulation. Installing a complete kit ensures all mating surfaces are fresh and seals are factory-spec.

Will this thermostat fit my 2011 Mercedes-Benz CL550 4MATIC?

Yes. The Genuine OEM 2782000815 is engineered for all 2011–2020 Mercedes-Benz models equipped with 4.7L and 5.5L V8 engines, including the 2011 CL550 4MATIC. Use the vehicle selector tool to confirm your exact year, model, and engine before purchase.

Can I replace the thermostat myself, or do I need a technician?

Thermostat replacement requires draining coolant, removing the thermostat housing, and reinstalling with proper gasket seating and torque. Most DIY enthusiasts with basic mechanical skills can handle this repair using a socket set, gasket scraper, and torque wrench. Consult your service manual for exact locations, drain procedures, and torque specifications. If you are uncomfortable working with the cooling system, professional installation is recommended.

What coolant should I use with this thermostat kit?

Always use Genuine Mercedes-Benz coolant or an equivalent meeting the Mercedes-Benz specification (typically MB 325.5 or later). Do not mix coolant types. Refer to your owner's manual or the coolant reservoir cap for the exact specification required for your model year.

How long does a thermostat typically last in a Mercedes-Benz?

Thermostats generally last 80,000 to 150,000 miles, depending on driving conditions, coolant quality, and maintenance. Thermostats in high-heat environments or vehicles with infrequent coolant flushes may fail earlier. If you are replacing the thermostat, consider also inspecting and potentially replacing the water pump and coolant hoses as preventive maintenance.

Order the Genuine OEM 2782000815 engine coolant thermostat kit today. In-stock orders ship same or next business day from our U.S. warehouse, and our fitment team is one call away if you need help confirming the right part for your Mercedes-Benz.

Note: All information on this page and in the FAQ is for general reference only. Verify fitment and consult a professional as needed. eEuroparts.com is not responsible for incorrect part selection or installation.