2003 Chevrolet Tahoe Change Coolant
Keeping the Dex-Cool coolant full on your 2003 Chevrolet Tahoe is an important maintenance step in ensuring damage does not occur to the heating and cooling system. While a coolant flush is a superior service to draining and then filling the radiator, allowing the coolant to run low in between services can cause severe damage. If regular flushes are performed on the full-size SUV, and the correct coolant is used, adding coolant in between should occur minimally, unless the system has a leak.
 Tools Used
|Coolant drain pan|
|Dex-Cool anti-freeze (pre-mixed)|
 Put a Coolant
- Park the Tahoe on a level surface and allow the engine to cool down. If the engine is hot, allow at least a couple of hours to cool down.
- Open the hood and locate the radiator cap on the left hand side (facing the engine compartment of the vehicle).
- Align the anti-freeze drain pan under the short radiator neck and cap beneath the front bumper of the Tahoe.
- Press the radiator cap inward then turn it counterclockwise slowly.
- Insert a funnel into the neck of the radiator and add pre-mixed Dex-cool anti-freeze (coolant) slowly into the funnel. Allow up to 30 seconds or more for the coolant to purge down into the radiator chambers. Add more coolant as necessary.
- Continue to add more Dex-cool coolant into the radiator until the radiator neck shows coolant about 1/2 inch down from the top of the filler neck and no longer drains into the radiator.
- Inspect the level of the coolant reservoir to the left of the radiator neck and ensure it's full. If it is not, remove the cap of the reservoir and fill it with pre-mixed coolant until it reaches the full cold line stamped on the outside reservoir housing.
- Start the engine of the Tahoe with the radiator cap off of the radiator if you added more than 1/2 gallon or more of coolant. There might be air in the system which needs to be purged from the radiator.
- Allow the engine to idle until it reaches operating temperature. In the meantime, monitor the purging coolant, making sure it falls into the drain pan and adding more to the radiator as necessary.
- Continue to monitor the progress of the purging fluid until it stops. Replace the radiator cap then top off the coolant reservoir again.
- Shut off the engine and recheck the fluid level in the radiator neck. If necessary, top the coolant off once again then replace the radiator cap.
- Drive the Tahoe within a three to file mile radius from where it was parked. Monitor the temperature gauge on the instrument panel inside the interior of the Tahoe while driving. Allow the Tahoe to reach optimum operating temperature then bring it back to its parking spot.
- Allow a couple hours to pass for the engine to cool before removing the radiator cap. Top off the radiator and reservoir again if necessary.