lmao im with ya..truck runs just fine without it.
It will run better with it.
What seafoam does is break up the carbon that builds up in the intake manifold, and the gunk that builds up on the valve heads.
Have you ever taken off the throttle body on your truck and looked at all the crap that's built up in there? That crap kills performance. It limits airflow, and it clogs up the vacuum ports in the throttle body. The seafoam soaks into the carbon buildup, breaks it down into sludge in a matter of minutes, and when you restart the engine it will suck all that crap down and burn it off.
It doesnt hurt the engine in any way, and the only way it will mess up your spark plugs, is if you needed new ones to begin with. For an engine with high miles which has never had the intake manifold cleaned, this works almost like a mild port job. It can/will improve idle stability, feul economy, and engine performance.
When added to the gas, it works basically the same way feul system cleaner does. But it will also lubricate the pump motor and injectors so they work more efficiently.
When you put it in with the oil, it helps prevent buildup of sludge in the crankcase, and will clean out the oil passages throughout the block. If you have a sticky lifter, seafoam will break down the gunk that is causing it to stick and free the lifter so it will operate normally. It will also condition the seals in the engine, preventing then from dryrotting and leaking.
I use this stuff all the time in my car. Havent had any trouble with it in the year and a half that i've owned the car.