'96 K1500: how can I tell fuel tank capacity by physical dimensions?

[DennisT]

My 1996 K1500 has a 6-foot box. Somewhere I thought I read that box size limited fuel tank size to the smaller tanks, (were they around 20 gallons??) Is there a way to crawl under and measure tank size and verify capacity? I would think it would be easy to visually tell the difference. And the big tanks I think were 34 gallons. Thoughts?? Thank you, Dennis

 

[fancyTBI]

long beds had 34 gallon tanks. Short beds got 25 gallons. Yours would have the 25 gallon tank. The 34 gallon tank won’t fit in the short bed trucks.