I have a 98 chevy Z-71 with a 4L60E transmission. The transmission is about4 years old bought brand new from dealership. My problem is it won't go into Overdrive or Drive from park reverse or neutral. When I take off I have to put it down in 1st or 2nd gear then put it up into drive or overdrive. All the other gears works good. It shifts good after you get it in drive or overdrive. Any thoughts.......

http://www.chevytalk.org/threads/postlist.php?Cat=0&Board=UBB70

Someone here may know, but you may want to try this Chevrolet truck forum as well. I was a member there when I had my Suburban.

Above is the direct link to forums covering the year of your truck.

The transmission is in limp mode, it has to be scan for codes.