Truck stalling out after switching to primary tank

[71threequarterton]

Originally Posted by LongBox

I was under the impression that you'd only had the truck for a couple of months, and perhaps did not have knowledge of how the previous owner used the two tanks.

Yes, I have only had the truck for a couple months or so. Unless the previous owner was BS'n me, he said the auxiliary tanks worked fine and he used them. I've only used the one on the driver's side and it works fine - I can switch back and forth from the auxiliary and primary on the fly - actually did that on my first drive home when I bought it - no problem at all. But what I've noticed now, is the two times that I've run off the auxiliary tank for a while, as soon as I switch back to the primary, it stalls out on me. I'm gonna start out by checking the filters.