Engine/Exhaust braking?
Check this thread: http://www.ecodieselram.com/forum/threads/factory-engine-braking-feature.482/
Welcome to the forum, we're glad to have you!
I haven't heard anymore recent reports, are all others being held as well still? I know GM still hasn't released the 2017 Duramax yet as well. Ford's '17 Powerstroke is out on the market already however.
Sorry to hear of the bad luck. Was the truck new when purchased? We've had a lot of member with oil cooler failures but it seemed like it was mostly 2014's.
Stick with the recommendations in the manual. Change your fuel filter more often than not.. use the correct oil as the TSB has changed it from the Euro Spec.
For performance, a tune is the best but you have a risk of loosing your warranty in event something catastrophic happen.
Welcome!
Terrible the dealer didn't assist in the oil change.
I've ran MBRP products on previous trucks and never had an issue.. I wonder if all the pipes are like that or if you got a "Friday" product.
1250 degrees isn't terrible for a duramax engine. In fact, you'll see that temp while the truck is in regen mode (for 07.5 and newer). It's most likely you had an injector get hung and it burn a hole in the piston.
Maintenance, maintenance, maintenance. That's the biggest thing to worry about when having a diesel. Also, reading the forums and seeing what works for others and also what doesn't work is the best advice I can give right now.