My long bed carries 35 from the factory. Short bed carries 34 I believe.

 

never know. i was lead to believe from everything that I read that it would make a big difference even for my year/wheelbase. I follow the instructions exactly. Alas, just a mod I shall never see the benefit of.

 

The mod just lets you fill faster, it doesn't add any capacity. I can put 36 gallons into my 34 gallon tank, just takes a bit longer.

 

before i did the mod i could never put more than 33-34 gallons in. now 36 w/ no problem.

 

it does let you put more fuel into the tank. before there was absolutly no way to get that air bubble out of the tank. you can fill your tank up all the way to the filler neck and that air bubble would still be there. moving the vent to the top of the tank where that bubble was lets you fill up that bubble (~5 gallons). So when you fill all the way up to the filler neck, the entire tank is completely full with absolutly no room for expansion. even with the mod you are still going to fight foam, but just not as bad. It also helps if you shake the truck once it gets to the top.

 

here are some pics of the vent mod we did while installing the ad150 and dual cp3's on a 6.7




while we were there, we did the roll over vent mod too with a filter to prevent trash from going into the tank.

 

It added about 5 gallons to my capacity.

 

I can put 36 gallons in now, there is no way I would be able to put over 40 with the vent mod......

 

What is the roll over vent mod for---is it a racing requirement?

 

Prevents it from leaking if you roll over. You should put a hose and filter on it so no trash can get in. I was able to get over 36 gallons in mine before the vent mod. Now I get 40 gallons in. You would be shocked how much room it makes available.