2003 Ford Mustang Owner Guide 5th Printing - Page 172

Maintenance and Specifications 15. If necessary, add a 50/50 mixture of engine coolant and distilled water to the engine coolant reservoir until the coolant level is at the "cold fill level" as listed on the reservoir. If you are unsure of how to operate the cooling system vent plug when adding engine coolant to the 3.8L V6 engine, contact your dealer. Engine coolant refill procedure-4.6L V8 engine The following procedure should be used when refilling the cooling system of a 4.6L V8 engine after it has been drained or become extremely low. 1. Remove the pressure relief cap from the engine coolant reservoir as previously outlined. 2. Slowly add a 50/50 mixture of engine coolant and distilled water to the engine coolant reservoir until the coolant level is at the "cold fill level" as listed on the reservoir. 3. Reinstall the pressure relief cap. 4. Start and idle the engine until the upper radiator hose is warm (this indicates the thermostat is open and coolant is flowing through the entire system). 5. Shut the engine off and let it cool. 6. Remove the pressure relief cap from the engine coolant reservoir as previously outlined. 7. Add a 50/50 mixture of engine coolant and distilled water to the engine coolant reservoir until the coolant level is at the "cold fill level" as listed on the reservoir. 8. Reinstall the pressure relief cap. 9. Check the coolant level in the reservoir before you drive your vehicle the next few times (with the engine cool). 10. If necessary, add a 50/50 mixture of engine coolant and distilled water to the engine coolant reservoir until the coolant level is at the "cold fill level" as listed on the reservoir. After any coolant has been added, check the coolant concentration see Checking Engine Coolant section). 172 2003 Mustang (mus) Owners Guide (post-2002-fmt) USA English (fus)