Sluggish 02 dodge ram 1500 4.7L

2002 3rd Gen 4.7L Dodge Ram 1500 SLT Quad Cab - Auto 4WD

The truck has been running real sluggish. Shifts gears in high rpm's and has difficulty going up a very steep hill by my home. When going up the hill it won't go past 30mph.

So far I've: Switched out all spark plugs and coil packs, replaced the alternator(not associated with the issue), and replaced the oil filter/air filter.

What am I not thinking of, can't think of anything else to replace to get this truck back to its former glory.

Try posting this in the 3rd Gen forum, you'll probably get better responses

It's in 3rd Gen now.

Instead of throwing money at things that aren't the problem, maybe try a trip to a trusted mechanic. Hard to diagnose and mostly you're going to get different things that vexed other but which may have nothing to do with your issue. But to get some additional comments, more information will help. Such as, has this been a long term problem, is this new to you truck, if new problem did it start after filling with gas or some other service, have you run for any codes, why did you replace what you did. Essentially, having a detailed history of how it started and when, how long it has been going on, and differences in performance under varying conditions. There are some pretty knowledgeable people here who might be able to help.

Good luck.

Thanks @JoshsRam and @rule18, new to the forum, and missed the 3rd gen forum, thanks for moving it.

Thanks for the tip @tron67j
Why Not Take it to a Mechanic Yet: I bought the truck as a secondary vehicle. I got this specific truck because I was told they were really easy to work on and I wanted to get a grasp on some basic mechanics. Learn to fix vehicle issues on my own. Also now, with the help of a forum hopefully.

When Issue Occured: When driving it after first getting it, everything was running just fine. The check engine lights were on, bank 1 and 2 miss fire. They would turn on and off and I didn’t go in to get it fixed right away. After putting a few thousand miles on, and going up a very steep and long hill the check engine light flashed and the performance immediately dropped. The truck accelerated and wouldn’t go over 30mph while I made my way up the hill to my house. I parked the truck at home and started to work on it.

Performance Issue: It feels like it drives okayish when on flat terrain, but it’s acceleration is about slower than it was previously. On a long enough road it’ll get up to full speed. Just takes a while. Going up hills its about the same but it waits till higher rpms to shift. But going up one specific hill that’s particularly long and steep it won’t go over 30 miles per hours.

Codes were bank 1 and 2 misfires, I consulted with an out-of-state mechanic buddy who said the sparkplugs needed to be replaced so I replaced the sparkplugs and coil packs. That cleared the codes but the problem persisted.

The next step was to just do some routine maintenance things to knock them off the list of potential issues. I changed the oil filter and air filter. The alternator was replaced because the truck stopped turning over.

I recently posted a very similar issue.
Looking for answers.