Ford Mustang Owner's Manual page 179

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).
179
2004 Mustang (mus)
Owners Guide (post-2002-fmt)
USA English (fus)