Gates 34299 Engine Coolant Thermostat

Heavy-Duty Cooling Control

Gates 34299 is a heavy-duty engine coolant thermostat built for demanding cooling systems in trucks, buses, tractors, and other equipment. Its steel and copper construction, O-ring seal, and jiggle pin weep hole support stable coolant regulation in harsh underhood conditions.

The Gates Heavy-Duty Thermostat line is engineered for applications where vibration, heat cycling, and long service intervals place extra stress on the cooling system. Part number 34299 is a bottom by-pass thermostat with a 190°F opening temperature for controlled warm-up and consistent operating temperature.

Key Features

• Engine coolant thermostat for heavy-duty cooling systems
• Bottom by-pass design for the specified cooling circuit layout
• Steel and copper construction
• 190°F start-to-open temperature
• O-ring seal type for a secure seal at the housing
• Jiggle pin weep hole for air bleeding during fill and service
• Compatible with applications cross-referencing Gates 34299

Product Details

Gates 34299 is part of the Green Stripe Heavy-Duty Thermostat family, a product line focused on durability in severe-duty environments. This thermostat is built for heavy-duty truck, bus, tractor, and heavy equipment cooling systems where noise, vibration, and harshness can affect thermostat performance. The 34299 thermostat uses a bottom by-pass configuration and a 190°F opening point to help the engine reach and maintain the intended operating range.

This part cross-references Four Seasons 15209 for the same application. It is also referenced in heavy-duty cooling searches for Gates 34299 thermostat, engine coolant thermostat 190 degree, and bottom by-pass thermostat for truck and equipment service. Compatible With heavy-duty truck, bus, tractor, and heavy equipment applications where this thermostat specification is required.

Common Problems This Part Can Address

• Engine running too cool or taking too long to reach operating temperature
• Temperature fluctuation caused by a worn thermostat
• Coolant flow control issues in a bottom by-pass cooling system
• Air trapped in the cooling system during refill or service
• Seal leakage at the thermostat housing interface

Installation Notes

Verify the thermostat style, opening temperature, and by-pass configuration before installation. Clean the housing sealing surfaces thoroughly and inspect the O-ring seat for damage or corrosion. The jiggle pin weep hole should be oriented according to the service procedure for the application. No installation tool is included.

For vehicle-specific searches, this part is commonly referenced in Gates 34299 thermostat lookup queries for heavy-duty truck and equipment cooling service. Confirm the cooling system specification before replacing the thermostat on any make or model.

Quality Assurance

Gates designs the Heavy-Duty Thermostat line for the vibration and heat demands found in commercial and off-highway cooling systems. Part number 34299 follows that heavy-duty construction approach with steel and copper materials, an O-ring seal, and a service-friendly jiggle pin design.