I have a 2001 Sport 1500 5.9l V8 and i noticed that when im going over 50 and my foot is not pushing down on the pedal (just staying steady at 50 or up) the truck starts to rev by itself. Its the weirdest thing it makes a rev noise like every 5 seconds until i let off the gas or go below 50 mph. Im praying its not a tranny problem the truck has got 116k on it. Anything helps.
Thanks

 

Probably Torque converter clutch engaging/disengaging. Check the throttle position sensor. That's the usual cause.

Welcome to DF.

 

Thanks man. And how do i go about checking it?

 

By looking in the FAQ/DIY section and downloading the free 2001 service manual, and getting a Haynes manual. However, I'm thinking blown plenum gasket , clogging cat and hosed o2 sensor. Read the plenum sticky on top of the forum.