I have also changed the oil at 10 vs. 20k and always with the dealer. Got car back after the turbo replacement. Was told over $10k in parts and likely equal amount of labor at rack rates. Thankfully under warranty. Drove for about 200 miles and check engine light came on. Took back to dealer. They drove it for a over a hundred miles for testing. Got a call yesterday that one piston consistently loses compression and JLR has approved an full engine replacement. Currently waiting on the engine to cross the pond and then the install. I'm a surprised that JLR hasn't simply totaled this car at this point. I know what KBB says its worth and the engine and turbo and other components together with labor likely exceed the value.I hate to hear this, There is really no reason for it, unless its blocked or insufficient lubrication. We are in the mid 30's mileage wise and still running great. I change the oil at 10K vs the 20K they want to run. Keep us posted if they state a cause like "bad turbo from factory, etc.."