HELP needed with GMC transmission problem

My 2000 Sierra just started having a problem with a server jump from
1st to 2nd gear.
When starting from a dead stop and my automatic goes from 1st to 2nd
on take-off, I get a very bad jumping jerk of the truck.
All other gears are good.

To get around the problem I began starting off in 2nd gear from a dead
stop.

Any help is appreciated.
Terry in Texas

"Terry" wrote in message

> Any help is appreciated.
> Terry in Texas

Have you tried adding a small amount of brake fluid to the transmission
fluid? It will smooth out rough automatic shifting.