Gates 34821 Engine Coolant Thermostat

Integrated Thermostat Housing for Mercedes-Benz

Gates 34821 is an integrated housing thermostat built for precise coolant temperature control in select Mercedes-Benz diesel and gas applications. It is an OE Exact replacement that follows the original housing-style design for direct service on vehicles such as the Sprinter 2500, Sprinter 3500, ML350, and E350.

The Gates Integrated Housing Thermostat line focuses on accurate temperature regulation as more modern engines use integrated thermostat assemblies. Part number 34821 is engineered as a direct aftermarket alternative to OE dealership parts for the listed Mercedes-Benz applications.

Key Features

• Integrated housing thermostat design
• Start-to-open temperature: 189°F / 87°C
• OE Exact comparison rating
• Check valve included
• 3 bolt holes for mounting
• 1 seal included
• Outlet inside diameter: 1.665 in
• Non-electric thermostat design

Detailed Product Overview

This Gates engine coolant thermostat is built to regulate coolant flow at the specified opening temperature so the engine can reach and maintain proper operating temperature. The integrated housing format helps match the original cooling system layout used on many Mercedes-Benz Sprinter, GL350, R350, ML350, ML320, GL320, and R320 applications. If you are replacing a worn thermostat housing on a Mercedes-Benz Sprinter 2500 or Mercedes-Benz E350, Gates 34821 provides an OE-style service part with the correct housing configuration.

This part cross-references Bosch 62389 for the same application.

What It Helps Address

• Coolant temperature that stays too low or runs too hot
• Delayed engine warm-up
• Temperature fluctuation from a worn thermostat assembly
• Coolant flow control issues in integrated housing systems
• Service replacement for leaking or aging thermostat housings

Installation Notes and Fitment

Compatible With: Fits 2014-2022 Mercedes-Benz Sprinter 2500, N/A; Fits 2014-2022 Mercedes-Benz Sprinter 3500, N/A; Fits 2018-2022 Mercedes-Benz Sprinter 3500XD, N/A; Fits 2011-2013 Mercedes-Benz E350, N/A; Fits 2010-2013 Mercedes-Benz Sprinter 2500, N/A; Fits 2010-2013 Mercedes-Benz Sprinter 3500, N/A; Fits 2010-2012 Mercedes-Benz GL350, N/A; Fits 2010-2012 Mercedes-Benz R350, N/A; Fits 2010-2011 Mercedes-Benz ML350, N/A; Fits 2007-2009 Mercedes-Benz ML320, N/A; Fits 2007-2008 Mercedes-Benz GL320, N/A; Fits 2008 Mercedes-Benz R320, N/A.

Verify the OE temperature specification and housing style before installation. The integrated design uses 3 bolt holes and a single seal, so the mating surfaces should be clean and free of old gasket material before reassembly.

Quality Assurance

Gates develops aftermarket thermostat solutions for integrated housing systems with OE Exact comparison standards. Part number 34821 is built to match the original application requirements for temperature control and housing fitment in the listed Mercedes-Benz models.