Gas Recirculation Valve (egr Valve) problems of the 2017 GMC Canyon

Oil leaking from a high pressure oil line. It was a pin hole in middle of line, rubber part located between radiator and engine. It was discovered after being parked for an hour in driveway, after a 100 mile drive. It happened while driving because the oil was everywhere around engine and on inside of tires. This was a very significant leak. Lost pints of oil. When I started car to check for leak it could be clearly seen pushing out with pressure. The placement of this hole makes it hard to beleive that anything could of punctured it. From some searching it seems this is not an uncommon problem. There are claims that the burst is due to starts in cold weather. The day it happened was 1/1/21, it was cold but not extreme I would say low 30's f I am filing this after truck was brought to shop, I did not take pictures or video, regrettable. Of course this was (is) a major inconvenience, a mess in driveway etc. But I consider myself lucky that my engine did not go on fire. Feel free to contact me for additional info.

Nox sensor position 2 failed, second occurrence, diesel vehicle entered limp mode. Limp mode is dangerous and indicated def fluid issue. This is a false positive (as described in many places on the internet and by the dealer) as a result of the sensor failure. First dealer did not stock the part, dealer 178 miles away had the part in stock. Limp mode is a continued decrease in vehicle max speed. While a failure of the exhaust system is critical, it should not be allowed to place an owner at risk. By the time I reached the second dealer, I had 4 miles until the vehicle would degrade to 4mph. I was asked to leave without execution of a critical step, because gm documents did not recommend that step as part of the repair. 2 scenarios exist, sensor failure without limp mode and failure with limp mode. In limp mode the vehicle cannot be driven long enough to reset the failure and gm should include this in the remediation. Incrementally, the dealer should have a process to reset limp mode to allow travel without this mode until the next ignition cycle. Also this would be a preferable service from onstar. The limp mode is great for the casual issue but creates a risk to life and limb for travelers and should have limited over ride capability. Being the failure happened on a major highway, in a construction area with concrete barriers on each side this created great stress. No american should own a vehicle costing $41000 that leaves you at risk or stranded. This is irresponsible.