IF you want to never exceed 3000rpm for example, you need a vehicle that has significantly more power under that. A Big block or forced induction will do that, like Ford's Ecoboost or a diesel. If you have 2WD, change the gearing to 4.10 for $500 and see if you like it. Otherwise, save your $ for a more capable truck.
Not true per se'
I have the 4.3 vortec 6 cylinder in my old 96 s10.. This truck has 3:73 gears. I only have 190 HP and 250 ft lbs of torgue..
The funny thing with these 4.3' is they make all the torgue at 2800 RPMs. This is why I can pull the 4400 lbs camper I have.. Not saying im winning races, but I can get going pretty good.
Torgue converter locks in and all is good and truck runs cool. Its when the TC unlocks then things may run a little hotter, but by that time im over the hill and it cools down quite fast. Trans temps never pass 190f and enginge temps the same.
65 in third im right at power band 2800 rpm..
Now as stated the OP's truck at 4000 rmp making all the power may sound like the truck is screaming... This is just what it is for the higher reving motors. Most gasers are like this..
As stated a diesal will net you lower rpm's and max torgue.
I would be more concerned with your trans temps and engine temps..