'97 auto HARD shift

Hey, I have a '97 1500 5.7L  auto,  After driving at a steady speed for a few miles, the first to sec. shift feels like a sledge hammer.
Cutting the truck off for a few seconds stops this for a while.
Would a chip that could program shift points help?
Thanks in advance.
David

Welcome to the forum!!! how many miles are on the trans?

Thanks for the welcome.
215 K,   the problem has been around since about 60K,  Sure keeps people from wanting to borrow it.

It may just be that way, my '95 shifts pretty hard, and I just had the trans rebuilt. Does you trans doing any other strange things?

David,
 
Are you getting a service engine light?  The "1-2 bump" is sometimes accompanied with a P1870 (transmission component slippage) code. 
 
You can find kits on ebay and from online vendors to fix the problem. 
 
http://item.express.ebay.com/Vehicle-Parts-Accessories_Car-Truck-Parts__TRANSGO-4L60E-4L60-E-SHIFT-KIT-GM-CHEVY-TRANSMISSION_W0QQitemZ4575138410QQihZ002QQddnZVehicleQ20PartsQ20Q26Q20AccessoriesQQadnZCarQ20Q26Q20TruckQ20PartsQQcmdZExpressItem
 
Don't know anything about this vendor or this kit, but here's one that's on ebay now.

Thanks for the info. There are no service engine lights on.
 
Also no other problems, no slippage,noises.
 
Thanks