New to the forum and just wanted to add my "experience" with the DEF issues.
I have a 2011 Denali HD with the new generation Duramax.
I live in Alberta and work all over western Canada. We get real blasts of winter of winter up here in the frozen north.
I was just - 38C (without the windchill) where I was working last week.
The DEF system is a complete joke for cold weather environments.
I cannot believe that GM engineers decided upon such a system for use on vehicles that will be introduced to such conditions. Urea and distilled water? That is a great idea.
My truck is currently in the shop for the fourth time in 27,000 km for DEF related issues.
It has completely frozen up twice and other times it was the sensors (or some other DEF related component) acting up due to the figid temperatures.
The tank has been dropped twice and all the current GM computer flashes have been completed. Probably another one will be done today.
I can no longer drive this truck in confidence and am always wondering when something will happen again.
I have driven GM all my life and this is in fact my first ever diesel engine. I pull a trailer so the added power is fantastic in every way.
But this DEF situation has gotten me to a point where I am now losing money by missing meetings etc...
I see most of the posts are from down south.
Please put the word out to anyone thinking about purchasing a truck with the Duramax engine NOT to consider it if they live in a very cold climate!
Trust me it is not worth the grief or the blood pressure flucuations!
Signed: One very, very disappointed, disgusted and fed up GM customer!
Odds are if a company makes 100k trucks, at least 1 of them will have a problem. I don't know how many trucks GM makes a year, but I'm guessing they've sold a good number of LML trucks if they just re-hired 700 people to make these trucks.
DEF is a solid known problem that GM seems to be working on. The other problems, seem to be the exception to the rule.