help

For some reason, on my '88 caravan, the transmission shifts way too quickly (3.0L V6). when I go and press the gas to go forward, it almost immediately goes to its 3rd gear (its a 3-speed AT)... any advice to what is causing this problem? any answer will be greatly appreciated, and hopefully it doesnt lead to buying another transmission (this is the 2nd transmission the van has ever had).

squarehead :banghead: