Peterbilt 379 fuel tanks not staying level

I have a 379 that will not stay even. We have tried to change everything. Hoses, splitter valves, tank vents, and pickup tubes In the tanks. It still seems to suck out of one tank for the most part. So I am curious on peoples opinions on putting a tank selector valve in the system so it would only suck and return to one tank at a time. Just looking for some feed back on the idea. Thanks

 

If you've replaced everything first make sure all your return hoses are the same length and routed so they are all at the same height. And difference if restriction will cause it to return to one side. If everything is right I'd just put #### off valves on the returns and whichever one is returning more just close the valve down half way or so. Play with it till you get them returning even

 

I drove a 1999 379 that did that too. Sucked fuel out of drivers side to passenger side, to the point of causing it to overflow…got stopped by a local cop due to the leaking fuel. I was worried about a hazmat situation.

 

Return lines are exact same length and both the same levels. We talked about installing taps on the top of the tanks as well to throttle back the tank that is getting to much fuel

 

Should be the same as a KW. Draw and return from both sides go through the same valve. They screw up now and again and return more fuel to one side.

 

Yea it’s the same as a KW. They do mess up and it’s annoying lol

 

I probably should have added I’ve had problems with new ones. I’ve learned that just because I put a new one on doesn’t mean it’s not ####ed up too. Changed 3 on one truck before I got one that worked right.

 

3 of the splitter T’s for the return line???

 

The valve that the draw and return go through. I’ve had a few new ones now that were bad out right out of the box. One was fubared totally. Changed it, and I started the truck the next morning and went for breakfast. When I got back one tank still had snow on it and the other was bare and dry. Brand new valve and it only drew and returned to one side. The others just didn’t draw and return equally like they’re supposed to.

 

2022 389 got the same issues as I had in older 379’s. I think they just are not right and Paccar engineering don’t care. Add more useless crap but don’t improve on basics…