So here I am again.... When I'm driving my 5 speed, usually in 5th and highway speeds, I put the pedal down and the rpm's go up but the truck doesn't accelerate. It doesn't do it all the time and it does it mostly in 5th gear. I know this is probably an easy diagnosis but I'm no mechanic so let's here some ideas!!!Thanks in advance!!!

Sounds like your clutch is starting to slip

my truck would do this, speed wouldnt change but the rpms would. changed clutch and no issue now lol

Yes sir, that is your clutch slipping.

I tend to agree the clutch is slipping.

Start saving. When my 5sp did this, I made it another couple hundred miles of driving at light torque levels before it stopped working. I just ordered a South Bend unit when it slipped and I could smell the clutch material burning.

i did a valair ceramic/kevlar and all the clutch guts/rear main, total was about $1000 and 12 hrs of me and a friend replacing it and the clutch guts/ rear main while i was in there.