Loud knock, ticking noise

[ChillyDog]

Over the past few days my truck has developed a very audible knock/ ticking sound that comes from the drivers side wheel well area. You can here it very loudly at idle and at slower speeds and it does it when warm or cold. I did a search and my guess is the lift pump? Truck has 81,000 miles and runs strong

 

[The patriot]

Could be the lift pump. Somebody told me that the overflow valve could be loud like this too.

I have some noise, but mostly when it's cold.

Eric