Gates 33329S Engine Coolant Thermostat

Gates Premium Thermostat 33329S Overview

The Gates Premium Thermostat 33329S is an engine coolant thermostat built for stable temperature control in a wide range of GM vehicles. It uses heavy-gauge stainless steel construction with copper components for improved corrosion resistance, plus an upgraded spring to help maintain consistent opening performance during normal operation.

Compatible With applications such as 2001-2006 Chevrolet Silverado 2500 HD, 1997-2006 Chevrolet Malibu, and 2001-2006 GMC Sierra 3500, this 195-degree thermostat is a direct-fit cooling system service part for many Buick, Chevrolet, GMC, Pontiac, Saturn, and Oldsmobile models.

Key Features

• Premium thermostat design for engine coolant temperature regulation
• Heavy-gauge stainless steel and copper construction for corrosion resistance
• Upgraded spring for improved temperature stability under normal operation
• 195-degree start-to-open temperature for OE-style cooling control
• Bottom by-pass design with O-ring seal type
• Seal included; no gasket required
• Gates 33329S part number for easy identification

Product Details

The Gates Premium Thermostat line focuses on durable construction and consistent thermal response. This 33329S thermostat is engineered with a bottom by-pass design, a 1.72-inch sealing flange outside diameter, and a 2.2-inch overall height. It is a practical replacement for drivers servicing cooling systems on vehicles such as the Chevrolet Silverado 3500, Buick Century, and Pontiac Grand Prix, where accurate coolant flow control is important for normal operating temperature.

This part cross-references Motorad 2067-195 and Four Seasons 59899 for the same application.

Common Problems This Part Can Address

• Engine running too cool or too warm due to thermostat wear
• Slow warm-up after cold starts
• Temperature fluctuation during normal driving
• Corrosion-related thermostat housing or valve issues
• Cooling system service needs on high-mileage GM vehicles

Installation Notes and Tips

• Drain coolant to a safe service level before removing the thermostat housing.
• Clean the sealing surface thoroughly before installing the new O-ring seal.
• Verify the by-pass design and 195-degree temperature specification before installation.
• Refill and bleed the cooling system according to the vehicle service procedure.
• Check for leaks and confirm normal operating temperature after startup.

Quality Assurance

Gates Premium Thermostats are built with stainless steel construction and an upgraded spring to support consistent operation and corrosion resistance. Part number 33329S is specified as a premium thermostat for confirmed applications across 1987-2007 Buick, Chevrolet, GMC, Pontiac, Saturn, Cadillac, Oldsmobile, and related GM platforms.

Fits 2001-2006 Chevrolet Silverado 2500 HD, 195 Degree; OE Temperature; Seal included; Premium Thermostat. Fits 1997-2006 Chevrolet Malibu, 195 Degree; OE Temperature; Seal included; Premium Thermostat. Fits 2001-2006 GMC Sierra 3500, 195 Degree; OE Temperature; Seal included; Premium Thermostat. Fits 2006-2007 Buick Rendezvous, 195 Degree; OE Temperature; Seal included; Premium Thermostat. Fits 2005-2006 Pontiac G6, 195 Degree; OE Temperature; Seal included; Premium Thermostat.