Ok so if you havent heard my truck isnt the great problems yada yada yada..... Ok so i heard from someone a tune up could help my problem.. The problem is the truck doesnt always want to shift it happens about every 6 times i start the truck up i get going at about 35 and it wont shift to the next gear it revs and revs but nothing. So i pull over turn off the truck and start it up again no probel what a shocker any suggestions or help would be appriciated.  

And what did you say you drove again? Year?  

Not sure but there is a sending unit on the rear axle by the rotor that sends info to the transmission on the speed the truck is going so the tranny knows when to shift. Mine went out on me and my truck did the same thing yours is doing. The part was $12.00 but that was 5 years ago.  

id check what IMVANISHINGBREED suggested, that sounds like something that would make sense? if your not mechanically inclined just take it in, im sure someone could be able to figure it out? good luck.  

if you haven't fixed the problem yet it could the clutch depending on the condition of your truck your clutch might not be enaging after you shift it into gear and take your foot off the clutch check that out just to be safe  

It is definetly a censor  sounds like the sending unit to the trnny from the rear axle. but before you go messin with censors  have your truck codes check with a scaner to make sure take it to a mechanic and have them hook u up to there machine and find out what is wrong before you make a costly mastake riping censors out...  

Does anyone know where to get a programmer or chip or any performance parts for a 02chevy silverado 4.3 v6

any help would be great