Ground wires to the transmission

I was going to say to start with checking the fluid level but I'm sure one of the three shops did that. The truth is that if you don't work on your own car you will need to bite the bullet and drop your car off with a shop for a complete diagnosis of the issue. This will require a hands on inspection and we won't be able to guess at the issue without looking at it. I suggest you use this link to find a good shop on our network. https://repairpal.com/repair-shops Alex