Originally Posted by ChooChooMan74
P20EE was common on the 14 EcoDiesels. They basically replaced all the 14's SCRs. Not saying that your SCR will be replaced, but it may need to be.
Now, what have you been running for DEF? Has it been sitting in the tank for long? I understand that the big trucks have smaller DEF tanks than the small trucks. If I am not traveling much, I will put a little in as needed. If I am traveling a lot, then I will fill up at the truck stop.
I've been using the Tech brand from Wally World, and have been keeping it full. Several mentions in my research say that it deteriorates faster in high temperatures. It is just below full right now, but my gauge is not accurate, apparently. Last time it was at this level, I took a trip and decided to top it off. It took a full 2.5 gallon bottle of the stuff and never looked back. So from now on I'm going to not add until it gets near empty, and only add 2.5 gallons at a time.
And......... the check-engine idiot light has not come back, so I doubt that it will.
And, I have 110 days until I get to retire from being a choo-choo man, myself.
(not that I'm counting)