How to Replace The Thermostat of a Peterbilt

If you had to pick a problem you’d never want your semi-truck to have you’d probably think of braking issues and a faulty engine. One common engine problem that should be a priority in prevention is overheating, and a broken thermostat may be the cause of it. Is this the exact reason you’re here? If so, let’s cut this intro short and get our hands dirty. If you want to replace your truck’s thermostat, make sure you follow the steps below.

Tools You’ll Need

Socket set and ratchet
Torque wrench
Screwdrivers
Drain pan
Replacement thermostat and gasket
Fresh coolant

1.Prepare the Truck

Make sure the truck is on flat ground and the engine is turned off. It’s important to wait for the engine to cool down. Keep this in mind!

2. Drain the Coolant

Before you can start removing the broken thermostat, you have to drain the coolant. For this you will have to open the radiator drain valve and the coolant will flow into the drain pan. You can take the used coolant to a recycling center and they’ll dispose it safely.

3. Access the Thermostat

Now it’s time to find the thermostat. It is usually located where the top radiator hose meets the engine. Disconnect the hose and unbolt the housing for easy access.

4. Remove the Old Thermostat

After you completed the previous step you can take out the thermostat and gasket. It’s good practice to check for debris or corrosion that would affect the new installation.

5. Install the New Thermostat

Place the new thermostat in the housing with the spring end facing the engine, then install the new gasket.

6. Reattach the Housing

Bolt the housing back in place and reconnect the radiator hose. Tighten bolts to the recommended torque.

7. Refill the Coolant System

Refill the radiator with fresh coolant. It’s important to run the engine to remove air pockets while adding coolant as needed.

8. Test for Leaks and Functionality

To finish it all, you’ll have to start the truck and check for any possible leaks. Also, it’s important to check whether the engine temperature can remain within the normal range

Conclusion

After everything is set and done, you should have an engine working within the right parameters, properly cooled off and most importantly, you did it all by yourself, saving a couple hundred dollars that you’d have spent on a mechanic. Stay safe and keep hauling!