I have a 98 chevy silverado extended cab has 5.7 350,and i think a 4L60E transmission. Driving around town my truck shifts fine, but when i get on the highway for a little while it will start jumping hard from 1st to 2nd, but if i kill the truck and start it back up it will usually shift fine. Any suggestions?
Common problem. Here is the few hundred $ fix.
http://www.chevytalk.org/fusionbb/showtopic.php?tid/199853/