if it has the tow haul mode that is probably what is causing it , the trans is designed to do that to reduce slipping when it shifts , this reduces the wear on the clucth packs an the it will last a lot longer
The most common cause of that is a bad EGR Valve.
fuse link
Oil leak and overheating?
It might be that you did not tighten the gas cap enough.
not enough freon or too much
yes, also no fuel pump and maybe a blown fuse.
Owners of Chevy Silverado's choose to lower their trucks for aesthetic reasons. There are no real performance advantages to a lowered truck, and in fact, if a truck is lowered too much, it can cause problems when driving over uneven terrain.
Nothing last forever. Replace water pump it's worn out.
if you have messed up the stiring wheel
Check the release switch that connects to the brakes. On many vehicles the brake light switch will cause the cruise to disengage. Next time, try pulling up on the brake pedal when you engage cruise. If it works when you're pulling up, you might be able to adjust the switch. It's physically connected to the brake pedal.
what would cause a oil pressure gauge to fluctuate on my 99 Chevy truck silverado i change the sending unit it does it mostly after it warmed up
You use a scan tool after repairing the cause of the code that turned the light on.