Gear shifter on the 2000 tacoma moves back and fourth when driving is this normal?

It's normal for the gear shifter on a 2000 Tacoma to have some movement while driving, especially if the vehicle is equipped with a manual transmission or if there's some play in the linkage of an automatic transmission. However, excessive movement or any grinding noises could indicate a problem with the transmission or shifter mechanism. If you're concerned about the amount of movement, it may be best to have it inspected by a mechanic for safety and functionality.