Not good... Engines absolutely hate it when they run hot and overheat.
That's the direction to investigate first - what's causing the hot operating temps / over-heating.
Question: how old is the engine coolant? Has it ever been changed?
A good investment in the health of your engine would be to have the cooling system flushed - get all the built-up crude and junk out.
Once that is under control, you'll be better able to assess for the 'rattle' - and whether it was caused by the hot temps, or possibly a critical, and more in-depth problem.
See "Related Questions" below for a guide on trouble-shooting the over-heating issue.
The recommended coolant type for a Ford Taurus is the green coolant. There are several different brands such as Prestone.
The engine coolant overflow reservoir is to the left side of the engine compartment. Checking levels, adding coolant, and coolant specifications are detailed and illustrated in the Owners Manual - See "Related Questions" below for more
by adding more gas I'm weak on Fords, but radiators are filled either at the radiator or the overflow bottle. The overflow bottle will be marked coolant only.
where is the engine coolant temperature sensor- low input locationon a 1998 ford taurus
A 2000 Ford Taurus has a coolant capacity of 11.6 quarts. This is in fact very close to 3 gallons.
The 1993 Ford Taurus coolant system has a fluid capacity of six gallons. The manufacturer recommends a 50-50 mix of water and anti-freeze.
The green stuff
It has several. Which are you looking for? Coolant? Windshield wipers?
overheating
On a 1997 Ford Taurus : The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap
On a 1998 Ford Taurus : The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap
I am not aware of a coolant bleeder valve on the Taurus/Sables.See "Related Questions" below for more about bleeding air from the cooling system.