Gates 33577 Engine Coolant Thermostat

Gates 33577 Heavy-Duty Thermostat Overview

The Gates 33577 heavy-duty engine coolant thermostat is built for demanding cooling systems that see constant heat cycling and vibration. It uses a Weir-Stat design with stainless steel, steel, and copper construction for dependable temperature control in heavy-duty truck, bus, tractor, and equipment applications.

For BMW M5 and BMW M6 fitments, as well as select Dodge Ram 1500, Ram 2500, Ram 3500, and Ford GT applications, this 170 degree thermostat supports OE-style cooling performance with a direct-fit service replacement profile.

Key Features

• 170 degree start-to-open temperature for controlled coolant flow
• Weir-Stat design for stable thermal response
• Stainless steel, steel, and copper construction
• Heavy-duty thermostat design for high-vibration environments
• Valve diameter: 2.27 in.
• Sealing flange outside diameter: 2.88 in.
• Height: 3.2 in.; height from flange: 1.6 in.
• No jiggle pin weep hole, no installation tool included

Detailed Description

Gates 33577 is an engine coolant thermostat engineered for applications that demand consistent temperature regulation under load. The heavy-duty construction helps the thermostat maintain reliable operation in harsh underhood conditions, while the Weir-Stat design supports accurate coolant flow control as the engine reaches operating temperature. This part cross-references Monroe Shocks & Struts 32247 for the same application.

Use this thermostat when servicing cooling systems on 2007-2008 BMW M5, 2006-2008 BMW M6, 2004-2006 Dodge Ram 1500, 1994-2003 Dodge Ram 2500, 1994-2003 Dodge Ram 3500, and 2006 Ford GT applications listed in the fitment data. The Gates 33577 part number is also commonly searched as a replacement thermostat for these OE-temperature applications.

What It Helps Address

• Engine running too cool or too warm due to thermostat wear
• Delayed warm-up after cold starts
• Temperature fluctuation from a sticking thermostat
• Cooling system service needs on BMW M5, BMW M6, and Dodge Ram trucks
• Thermostat replacement during overheating diagnosis

Installation Notes and Tips

Verify the 170 degree temperature specification and match the thermostat to the listed vehicle application before installation. Inspect the housing, sealing surfaces, and coolant condition during service, and replace any damaged gasket or seal components as required by the application. Confirm proper coolant fill and bleed procedure after installation to help prevent trapped air in the cooling system.

Quality Assurance

Gates designs its Green Stripe heavy-duty thermostat line for the vibration, noise, and heat exposure common in truck, bus, tractor, and heavy equipment service. The Gates 33577 is built with durable metal construction for consistent cooling-system control in demanding operating conditions.