I went to my GM dealer this morning. She gave me a copy of the 16-page directive that the dealers got called 'Product Safety - Unintended Ignition Key Rotation'. She said that my problem isn't something that is specifically covered by the recall. They said they will install 2 16mm key rings and either an insert in the key slot or a cover on all keys for the car. That seemed the cheapest way for GM to get out of this. But I had a thought. If the purpose of whatever they do to my car is to stop unintended ignition key rotation, and since my key is stopped from rotating normally, will whatever they do on Monday be something that will remedy my situation?

If I read this right, there is excessive wear in the linkage for the ign. lock. Where the tumbler drives the rack teeth for the connected switch linkage, or the switch.

GM is adressing issues on some of their cars, you could tell them your vehicle info over the phone to see if there is any campaign for your 140+ K mile vehicle? or it has just served a lifetime and a half.

I would say the tires are low and the rear differential is loose. But with no more information than you have provided it could be a million different things.

you have ignition problem nothing to do with the transmission