So I noticed since I test drove the truck that at low RPM, like when the brake is on and I am stopped, the truck vibrates ever so slightly. Runs smooth as can be once I get rolling, but around the 500 RPM range it is a bit shaky. I figured it wouldn't be a big deal to fix, if it was even a problem. It is only noticeable enough to bother me, not enough to cause me any real problems. I noticed, though that when I turn the AC off, and the RPM bumps up to about 900, no more vibration/shakiness. Turn AC back on, RPM drops to around 500 again and it vibrates. Any ideas fellas? Run some SeaFoam through it or...?
-EDIT- AC on when driving, no vibrations, only vibrates when stopped, so I don't think it is the AC compressor.