04 Stratus Tranny Problems

My Daughter has a recently purchased 04 Stratus with 95,000 miles.I had her boyfriend take it to a local shop for fluid and a filter.The shop boss tried to convience him that the tranny needed an overhaul. He saw the fluid was dark and had maybe a teaspoon of shavings in the pan.I've always serviced my own tranny's and this is what I call normal for the mileage.The problem is the car shifted fine before,and now after the sevice it shifts fine but shifts hard into the next lowest gear regardless what gear when they let off the gas. What could the shop have done to cause this? Any help would be appreciated.

Maybe nothing. I have seen this with a fluid change. The new fluid changes the way the transmission shifts. And yes sometime it means the transmission is starting to go bad. Try a pint of K+W transmission repair. Sometime it works.

Wrong fluid. They should have used MOPAR ATF+4 nothing else.