Hello, I have an 08 f450 and Im having issues with the front tank. The truck has an aftermarket fuel pump for the rear tank that works just fine. Whenever I switch to the front tank that pump keeps working but for some reason diesel is being transferred from the rear tank to the front. I have taken pictures and a video explaining the issues that im having. Ill be posting it on YouTube and the pictures here ( I cant upload the pictures for some reason ill try later from my computer). Thank you in advance.

Edit: Here is the link for the YouTube video explaining what’s wrong with the truck.

 

If factory dual tanks then you have a bad check valve. If it's an add on then it needs one installed in the pump discharge line from the fuel tank.

I don't have diagrams of this system so you'll need to get one to verify.

 

This is its aftermarket fuel pump and filters.

Tank selector switch, which apparently is working because when I switch from front to back i can hear the valve work.

Im guessing this is the original smaller fuel pump?

 

Bump bump Bump i need some help with this. thank you.