Fuel Issue 2003 Peterbilt

I have a 2003 Peterbilt 379. 6NZ CAT.

Symptoms

• In the past few weeks I've noticed fuel is coming out of the tanks at the caps.
  
  
• I changed the caps(new ones) it's coming out of both caps almost like the tanks have some pressure on them.
  
  
• New fuel tank breather valve and cleaned the hoses to them. and frankly all that seems to have made it worse.
  
  
• The fuel pressure has been at 80 since I've had the truck but shortly after I got the truck during a regular servicing Cat upgraded something on the fuel system
  
  
• I have cut offs on both tanks for the returns and service lines.The ball cut off valves haven't been changed since they were installed.
  
  The turbo boost presure runs about 28 (turbo has a waste gate). With the Pittsburg Power turbo the boost was about 32, that turbo had no waste gate.
  
  
• I have noticed that when I fill up, the passenger side tank holds 50% more fuel than the drivers side.
  

Any help would be appreciated as I am bumping my head here.

 

Yes out of the caps

 

That has been some what gradual as sometimes the truck wash people bump the cutoffs at the tanks and I don't always catch it in time but the passenger side does take more fuel than the drivers side.

 

I have reached out to Peterbilt factory for the fuel line schematics. I haven't decided 100% but I will probably bite the bullet and replace every line as it seems simpler to do that than spend a fortune "troubleshooting" the issue. Not to mention the age of the lines. I can get the new lines made locally. IF that doesn't solve the problem then I don't know what will.
What did you replace the lines on yours with? @Artic_Fox