What is the gear ratio for a 1998 Toyota Tacoma 4x2 with the 2.4 liter engine?

Since there isn't just one ratio available for each model it's tough to say. Inside your driver's doorjam there's a tag with a bunch of information on it. It contains codes for trim, color, options etc., and toward the end of the line you'll see a 3 digit code ending in an even #, most likely 4. The preceding 2 digits are the axle code, which you can reference on this site to see which ratio you have. http://toyota.off-road.com/toyota/article/articleDetail.jsp?id=274535