Ok i have been pouring through my chilton guide and cant seem to find out what this linkage does, and since it has been raining like a drunk monkey didnt want to climb underneath and try to trace it. So any info would be nice, hopeing this is what is causing my truck to not shift up at highway speed.

 

PS its the bottom one i am interested in, and its on a 5.7l c2500 1992

 

That cable goes to the trans throttle control valve and it does control shifting. Your manual should have the adj procedure in it.

 

would that be in my trucks manual or the chilton guide that i have?

 

Chilton,,your truck manual wont show any adjustments. Or Google it, Im too lazy to type that much.