I need to replace the tank straps (one finally rusted out). The truck is a 1983 standard cab, base, long bed with only the left side tank. I thought it was the 16ish gallon, but have seen it could be the 19.

Thanks

 

Long wheelbase trucks (133") have the 19 gallon side tank standard.

Short wheelbase trucks (117") have the 16 gallon side tank standard.

 

I bet you have been getting close to 16 gallons in it at the fuel station? If so, you do have a 19 gallon tank. You will never be able to use all the fuel in the tank. And since you have a long bed, as was mentioned you should have the 19 gallon tank.

 

Thanks all, it was the 19.