Free one year "trial subscription" not used, so I have no obligation?

My new Jeep game with a built in XM radio. I was never told about it by the dealer, and it never crossed my mind. I received a letter from XM, telling me that I had a free one year "trail" coming to me.

There was nothing about XM on the dealer sticker, and there was no agreement in the papers I signed. I never gave XM a credit card. I have no known legal relationship with XM.

Furthermore, I also never gave the dealer any permission to share my name, address, or any other information.

I was about two months into the free year, when I called XM. I asked them to cancel, but I do not think the Indian lady understood me. I logged on and deleted the radio from the account. I selected "opt-out" on all communication. I disconnected the yellow lead from the radio so that the stupid "weather alerts" would cease.

I am writing to XM, asking that my VIN, and all my information be purged from their database.

My question is this; will they try to harass me when the year is up. Will they "renew" and try to send me to collections? They have quite a reputation.