What is the gas tank size on a 1997 Chevy s10 truck?

18 gallons

Edited by Jimwhoski, owner of a 1997 Chevy S10

A 20 gallons tank, and only a 20 gallon tank, is mentioned in the Haynes Repair Manual #24071 for Chevy S10 Pick-ups (1994 thru 2004), Chevy Blazer & GMC Jimmy (1995 thru 2004), and Oldsmobile Bravada & Isuzu Hombre (1996 thru 2001)