[ewill3rd]

You can try another dealer and or contact Cadillac Customer Care. Express your concerns and try not to sound like you did in that post.
Sometimes stuff breaks. Tony is right your dealer is just not handling it the way you want.
If you want it done at that dealer start working your way up the food chain. Talk to the SM then if he doesn't help try the GM (General Manager).
It will work better for you if you bought the car there or have regular service history there.

If you pay someone else to change your oil and maintain your car or bought your car somewhere else it will be less likely that they will go out of their way to help you, although not impossible if they want your future business.