i read all the previous posts about the pump but not sure. anyway it was 98 degrees outside the other day for the first time and my temperature gauge went up to 210 for the first time. it usually stays at 175-180 ... so i was driving and all of a sudden i feel a quick jerk at 55mph i start hearing some whining noise that went up as the RPMS did. i pulled over to listen better and it sound like the transmission? but im not 100% sure. my volt gauge was also reading 10.5 volts...i turn off the truck for 60 seconds and restart it but no noise. i drive again and the noise came back after a few minutes...today and yesterday with 80-85 degree weather no noise. did i overheat something? or something on its way out?

 

Did you recently change the fuel pump?

 

nah, its got the original fuel pump in it. i checked the fuel pressure and its good. 60psi with the key on and 53psi running at idle. 2 lbs below the 55psi normal but thats because i have to change the spider and regulator....besides i hear the whining noise under the body cab somewhere, the only other thing other than the tranny that i can think of, is that the catalictic convertor might be clogged. i know it has been rattling for a few years now. so as of yesterday i started to stick a very long drill bit into it from the back to try to break it up so that when i start the engine the crap shoots out. i still have to finish it though.

 

Try removing the serpentine belt and start the engine and run for just a few seconds. If the whine is no longer there then you have one of the belt driven components that is at fault such as alternator or an idler pulley.