Chevy Shake- Random fix

[dasimmon]

You definitely need to take your truck in for service. When you do, ask why they recommend leaving it in Auto. I am interested in hearing what they say.

+1

[fondupot]

its an electronic transfer case so it's meant to be shifted on the fly. I never keep my truck in auto or 4hi for more than a few minutes at a time. Enough to gain traction during turns while in bad climate weather, but once you're going straight, no amount of 4wd will save you if you are going too fast.

[Thomcat]

It can save you in a torrential downpour where the blades can barely clear the windshield Auto/4WD is safer even when going straight. In 2WD the front wheels are passively rolling due to friction with the pavement. In a flooded roadbed once the sipes cannot clear the water fast enough, especially in worn tires, and a wedge builds up in front of the front tires, the front wheels hydroplane and you lose steering. In 4Wd the front tires are actively spinning and clearing the water from the sipes faster than static front wheels permitting a larger flow and preventing the water wedge from building up. And no damage to the tranny from the flooded surface either.

 

Easy enough to demonstrate the principle.....place a set of drive ramps on a smooth/slippery surface .....try to mount in 2WD and the tendency is for the front wheels to push the ramps ahead of the tires .....try it in 4WD and it will actively pull the ramps under the tires and climb the ramps.