hi guys, im new to this site but ive got a few questions that hopefully you can all help me with. i bought a 2010 silverado about 3 months ago and first off i noticed as soon as the tires start to spin it almost immediately shifts up, doesnt matter if i have traction control on or off. im sure its supposed to do this but id like know how to stop it. the second thing is when i put it in 4L the light just keeps blinking it never goes solid like it does in 4H. any input would be great, thanks.

 

Sounds like the selector switch, replace it.