Your profile tells me you were probably nine years old when this car was built. So, I'll speculate that you are not the original owner and not responsible for most of this car's maintenance. Chances are good your fluid change may have been the first.
Was the fluid changed in response to trans problems?
It's a French built GM trans that doesn't cost a ton to overhaul, if your car is as nice as it appears in your sig then probably well worth the expense.
Your frustration would be better directed at the car's previous owner or perhaps the kind of use it's had. That chip and K&N aren't for "babying" a car.