* 4-speed automatic: This was a very common option.
* 5-speed manual: Also a frequent choice.
To know for sure which transmission *your* specific 1999 Chevy S-10 has, you need to check:
* The vehicle's identification number (VIN): This can be decoded to reveal the exact specifications.
* The owner's manual: This will list the transmission type.
* The sticker on the driver's side doorjamb: This often includes information about the transmission.
* Under the hood: Look for a tag on the transmission itself that might identify it.
Without knowing the specifics of your truck, it's impossible to say definitively.