I had the same problem, a no power 3.0
Here is a thread with what I did to fix the problem and what I paid. My 3.0 was a dog. Comparatively now, it is a rocket. I have no issues pulling my trailer and without the trailer the thing flies. It throws me back in the seat, (just a little). It is not a 5.0, but compared to what I had, it flies.
I was having trouble getting the RPM's out of it, now I have no problems.
The major helps were: fuel filter, cat, cat back, Seafoam, and Walmart Gumout treatment. I have seen plenty of people laugh at that last one, but I know what it did within the first tank. (I went out to pick up something at 7-11 at midnight, I drove it around until around 3:00AM because I was so shocked by the difference. It was like a new truck.) If you do not have that problem, it will fix nothing, but my truck runs better now at 145K than it did at 66K when I got it due to the things I did.
My truck specs are on the other site. I have 4.10 gears, 30X9.50 tires, about a 3.93 final ratio.
http://www.ranger-forums.com/forum2/f5/f32/69568-light-trailer-no-towing-power.html
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Not to be a dick, but that's funny!
