What temperature should my Chevy 350 thermostat be?
The Chevrolet 350 typically uses a 195°F (90°C) thermostat, though some applications may use 180°F or, less commonly, 160°F depending on year, model, and climate. Always verify the exact spec for your vehicle.
Typical thermostat temperatures for the Chevy 350
The following temperature options cover common configurations you might encounter on Chevrolet 350 engines. They are not universal and should be confirmed against your specific year and model.
- 195°F (90°C) — Standard for most modern V8 350 engines in cars and light-duty trucks.
- 180°F (82°C) — Used on some models or in cooler climates to speed warm-up or improve efficiency; not universal.
- 160°F (71°C) — Rare in stock setups; appears in a few specialty builds or emissions-focused configurations; not generally recommended for typical daily driving.
For the average Chevy 350 owner, sticking with a 195°F thermostat is usually the best balance between quick warm-up, stable operating temperature, and emissions performance. Always refer to the factory spec for your exact vehicle.
Why thermostat temperature matters
Thermostat temperature influences how quickly your engine warms up, where it runs most efficiently, and how the cooling system manages heat during various driving conditions. Here are the key effects to understand.
- Warm-up and response time — A lower opening temperature means the thermostat opens earlier, helping the engine reach operating temperature faster after startup.
- Operating temperature range — Most Chevy 350 engines are designed to run around 190–210°F (88–99°C); the thermostat helps maintain that range by regulating coolant flow.
- Fuel economy and emissions — The engine control system tunes air-fuel mix based on temperature; an improper thermostat can cause richer or leaner mixtures and affect catalytic converter performance.
- Overheating risk — A thermostat that doesn’t open properly, or one that forces the engine to run too cool, can contribute to overheating or poor cooling system efficiency in extreme conditions.
In typical daily use, a properly functioning 195°F thermostat provides reliable performance and acceptable emissions for most Chevy 350 applications.
How to choose or replace your thermostat
If you’re replacing or upgrading, here are practical guidelines to follow so you choose the right degree and install it correctly.
- Confirm the exact spec for your vehicle — Check the owner’s manual, service manual, or GM service bulletins for your year/model to confirm the correct thermostat rating.
- Match the temperature rating — For most Chevy 350 engines, use a 195°F thermostat unless your manual specifies 180°F or another option for your climate or application.
- Gather necessary parts — New thermostat, gasket or O-ring, gasket sealant if recommended, and fresh coolant as needed.
- Prepare for replacement — Coolant drain, disconnect battery if working near electrical components, and have rag and solvent on hand to clean mating surfaces.
- Install correctly — Place the thermostat in the housing with the proper orientation (usually the spring side facing into the engine). Re-seat the housing with a new gasket, then refill coolant and bleed air from the cooling system.
- Test and verify — Start the engine, monitor the temperature gauge for a proper rise to operating temperature, check for leaks, and confirm the thermostat opens as the coolant warms.
Following these steps helps ensure a reliable install and consistent cooling performance. If you’re unsure, consult a professional mechanic to avoid cooling-system leaks or improper installation.
Summary
For most Chevy 350 engines, the standard thermostat temperature is 195°F (90°C), which balances warm-up speed, operating temperature, and emissions. Some applications may use 180°F or 160°F, but these are less common and typically specified by the vehicle’s year, model, or climate. Before replacing, verify your exact spec, and follow proper installation steps to maintain reliable cooling and engine performance.
