Rough Shifting after car wash
 

Hi. I have a 2005 Deville with 85,000 miles. Prior owner maintained meticulously. Eight hours ago, I drove it through the car wash. Immediately, it started shifting hard in every gear. Every shift there is a thud. Other than that it shifts properly. There are no lights on in the dash. I checked the transaxle fluid and it is full. Is there any way the car wash could have caused this? I take it to the dealer if it continues, but I am very worried it is a major transmission problem. If anyone has any thoughts about what might be going on I would appreciate them.

Thank you.

Before taking it to a dealer, take it to AutoZone and have them scan it for codes(they do this for free). If the trans is shifting hard, there will be codes somewhere. Post any codes they pull, and we can determine what to do next. It's possible that water got up into a connector somewhere and it causing this. If so, it might dry out, and start working OK again.;)

Thank you
 

Thank you for your message. Your comment makes great sense. Unfortunately, the transmission did not improve over ten days. It is so bad I am afraid to drive it to Auto Zone. I also don't have the facilities or tools to fix it if it is just a loose connector or something similar. I was really looking for some possible explanation of what might have happened. I am afraid I will have to take it into the dealer.