So I went ahead and stretched the spring the overflow valve. I attacked it from the top bolt (14mm), so after I removed the bolt, I saw the spring sitting inside and I took it out with a pair of needle nose pliers. I stretched the spring about 0.23" and put it back. I ended up losing the tiny washer that goes between the spring and the bolt but it doesn't seem to matter. Started the truck up and I got about 44 psi at idle and about 38 psi driving normally! After a while I heard my lift pump ticking and it was getting worse, so I pulled the spring back out and squished it between my fingers a few times. Put it back and I'm seeing about 23 psi at idle and up to 35 psi driving. I don't hear the ticking anymore either. It was very easy. If it weren't for me searching for the tiny washer I could've had it done in less than 10 mins.

I did this along with my fuel filter and pre-filter and I my fuel economy went up from 13 mpg to 18-19 mpg! Truck feels like it's got more power too! Before it felt like the parking brake was sticking a little. I guess it was time. I'm just really happy that I got my fuel mileage back!

 

My experience is stretching the spring is a very short term fix, once the spring starts losing it's springiness it's never the same.
Break down and buy a new valve.

 

12V's like frequent fuel filter changes too. They are real finicky about it and will definately go downhill if the filter is dirty.

 

Glad to see that its worked for u

Keep us in tabs on this..

Rick