For comparison I have 2 Silverado's. One is a 2001 2500 2wd standard cab 8ft bed 6.0. My personal truck is a 2005 1500 crew cab 6ft bed 4wd with the same 6.0 engine.
Up a steep grade my older 2500 will pull up a hill with 3/4 throttle and maintain 80mph if I wanted to. Surpass it with ease if at full throttle. Where as my newer 1500 with the same engine and it being longer on the same steep long incline would be maxed out full throttle to maintain 70-75mph.
There is a huge difference between a light truck and heavy duty truck. Even with the same engines. As mentioned safety should be first. My 2500 tows a 4000# trailer every single day. My 1500 would get chewed up if I tried to do that. My brakes would be replaced monthly, my truck would deteriorate extremely fast. etc etc.
My personal truck is sufficient to tow it. And prettier so I do. So just know your limits. Your truck is fine and there is no need to go that fast in a truck not equipped to do so.
When I was a child, I used to talk as a child, think as a child, reason as a child; when I became a man, I put aside childish things.
1 Corinthians Chapter 13 - 11