I have a 2005 Tahoe 4wd 80000miles. For a while now I can be driveing the road and my Tahoe will just jump out of gear pretty much like its in neutral. I can try and put it in park and its like parks not there and reverse grinds. I have to put it in 4wd ^ or 4wd auto to get it to drive again. Then sometime I can take it back out and it will work and it may not.

Now my truck will not go into 4 low. It grinds and pops and grids and the button blinks. Never goes in to 4 low and I really would like to fix these problems. Can anybody tell what it wrong with my truck???

 

The biggest issues with the transmission have been the various electronic solenoids in the valve body failing. Doing the fluid and filter changes regularly will help in prevent them from failing due to debris in the valve body, but there is nothing you can do to prevent their failure due to internal electronic failure. The one really known issue is a failure in the ignition switch that causes a voltage drop to solenoids and causes the transmission to become stuck in between gears. Replacing the ignition switch resolves this issue.