The timing chain issue on these Lambda engines was known to GM and their solution was to reprogram the engine control module to avoid setting the Service Engine Soon light, and to shorten the oil change period so the chains wouldn't fail before the warranty expired. They also offered an extended warranty and free replacement of the chains with upgraded chains and guides and pulleys, for 10 years or 120K miles. I bought my car in 2015 from a Cadillac dealer with 67K miles on it, and due to my complaint about the engine balking at low RPM (at the time I picked up my vehicle) they immediately reprogrammed my ECM which supposedly resolved the problem, without telling me there was a special warranty to replace the chains with upgraded versions (supposedly because the problem was supposed to be fixed in 2010 models, although mine was built early in 2009 and never had upgraded chains).

Now the Cadillac dealer wants over $2000 to fix the chains (I've only put 105,000 miles on it), and says there are other problems with brakes, the hubs and reluctor rings (bad connectors), etc. and wants over $6,000 to fix it all. They say they won't give me more than junk value if it is traded in, and that they would donate it to a charity if they did take it as a trade in. They contacted Cadillac who says my mileage (172,000) is too high to be covered under warranty.