2011 Cadillac CTS lost power & engine locked, any ideas?

If a quick change oil shop was involved you may want to get a good shop involved to find out if they did something wrong during the oil change. But with that kind of mileage on this engine it still could be a internal engine failure like an oil pump, or head gaskets.

Thanks for the info, towed it into the caddy dealer today to check out.. Thx CF

Good luck.

: )

They'll tell you it needs a new engine for a gazillion dollars because it's 13 years old and they don't want to be bothered with it. Have them analyze the oil. I bet the oil change place messed up. But, unfortunately, and again, because the vehicle is 13 years old with 130,000 miles on it they're not going to take responsibility for their mistake. I suggest junk it and move on. Truthfully you're lucky to have had it this long. A Cadillac is just another GM. Jim

Sounds like your alternator died, and you didn't realize it. When you attempted to turn it back on, the battery would have been dead by then. Perhaps you can let us know how it went after it got towed.