Like the title says, when I start my ranger it idles really rough. If I give it gas it shudders like it's gonna die. After about 2-3 mins it smooths out. If I'm on the interstate and down shift to pass someone, while accelerating it feels like I have a misfire (no CEL given) not all the time though. I've changed plugs and wires and it stopped doing it so I thought I had it but, it continued a few days later. Then I changed the fuel filter and it stopped again for a few days. Well it's back again. I'm thinking it's the fuel pump but I wanted to check here before I take my truck bed off. I also checked for vac leaks and I'm all good there. Any ideas?

 

Welcome to FTE.
Even if you don't have a lit CEL, scan the vehicle computer/controllers for trouble code clues, with your ELM scan tool using a good program like FORScan, ect & post up All code Numbers.
Before throwing a fuel pump at the problem, use your fuel pressure gauge to test fuel pressure & volume over time, it should be something like 1/2pt/15seconds & 64+/-8psi.
Unless your bringing the vehicle up to date on needed scheduled maintenance, stop throwing parts at the problem, unless a trouble shooting result suggests it's bad.
Some thoughts for consideration, let us know what you find.