There were 3 different engines offered in most years of Taurus / Sable production, and each engine used a different filter (assuming the SHO & DOHC were different from each other).
The friendly folks at the auto parts store will be able to help you determine which filter is the correct one for your vehicle.
According to the 1999 Mercury Sable Owner Guide : ( 5W-30 )
What is a gem module for 1999 mercury sable? And what does it control?
Yep, sure does. See "Related Questions" below for more
On a 1999 Mercury Sable : The transaxle ( transmission ) is located in the engine compartment , bolted to the engine
The air intake filter assembly would be connected to the throttle body.
On a 1999 Mercury Sable : Relay # 30 is the Powertrain Control Module ( PCM ) relay
According to the 1999 Mercury Sable Owner Guide : ( 60.6 litres / 16.0 U.S. gallons )
1999 mercury sable horn replacement
According to the 1999 Mercury Sable Owner Guide : With engine oil filter change : The 3.0 liter Duratec ( DOHC ) V6 engine takes : ( 5.5 U.S. quarts of 5W-30 )
The ECM in a 1999 Mercury Sable is located on the inside of the vehicle on the passenger side. It is located under the kick plate.
According to the 1999 Mercury Sable Owner Guide : ( Motorcraft MERCON-V automatic transmission fluid ) ( to confirm the type used , it should be engraved in the automatic transmission fluid dipstick )
36R