05 auto
So my truck started an odd habit last week. start the truck and leave, once it hits 2k rpm it just stops revving up until it shifts a few seconds later and then it drives completely normal for the remainder of the drive until its shut off and re started. I had the batteries disconnected for a bit and it did it the first drive after hooking them back up, Im not sure if its connected but its the only thing out of the ordinary ive done.
Thanks for any help in advance

 

Try cleaning all ground connections, from batteries to chassis to body ground connections. There are several of them. A bad ground will raise havoc. Also make that cleaning an annual ritual as part of your maintenance. I would start there before moving on. Any codes? You didn't mention any, so Im assuming not.