Our 2000 LeSabre used to drink coolant like crazy. Turns out there was a coolant system leak covered by a recall. It's thirst for coolant was quenched by the recall. Make sure to check with your dealer to ensure the recall work had been performed. I'd wait for the vehicle to cool down, and open the rad cap to take a look-see inside to see if there is plenty of coolant (Dex-Cool is used on these models). If coolant is not there, top it off through the radiator (with 50-50 coolant/H20) and get over to the dealer ASAP.
2009 Honda Civic 400 Miles
2002 Lexus RX 70K Miles
2000 Buick LeSabre 65K Miles
1997 Lincoln Town Car 145K Miles
1982 Corvette 85K Miles