1993 F350 crew cab 4x. 7.3l w/banks. I have the dual tanks option on my truck. What is the total fuel capacity? Both tanks were showing empty yesterday but I was only able to put a bit over 26 gallons combined in the 2 of them.

 

Each one, I think, should be 19gall. giving 38gall total.

 

You also have a 93, the sending units could be going bad and giving you wrong levels to the gas gauge. Would also help fix the dual tank problems of the non-operational tank getting fuel fed to it, not sure if the diesels have that problem though

 

I think one is 18 and the other is 20 I read once either way its still 38 gallons.
Mine actually shuts off around 20 gallons and the other 23 gallons

 

I have never gotten more then 12 gallons in either tank on my crew cab, although I have never ran either tank completely dry just to find out what they do really hold

My reg cab is a different story, just put 22 gallons in the front tank last nite.....

 

Assuming your truck is a 168" wheelbase (longbed crewcab pickup) you should have 19 gal front & 18 gal rear.

 

That's the same capacities as my SC long bed..

 

I just noticed the OP has a 350, meaning long bed, so mine doesn't apply...