A couple of questions..

[Bengy88]

In my personal opinion.... and this is just an opinion.
I really dont see how anti gel would cause damage to the doc/dpf. Im not going to say it doesn't but im definately not gonna say it does.
In my personal opinion good oil is good oil. Rawze and I just had this conversation. As long as you are using a good oil and servicing your truck regularly.... Based off of fuel mileage then you will be just fine running delvac, unless you are in extreme cold temps dont waste money on synthetic oil, and lucas is over rated bullshit.
I wouldnt recommend idling at 7k rpm as most diesel engines do good to ever see 2.5k rpms at wide open throttle lol. Assuming you mean 700rpm if i was in extreme cold temps i would idle my truck up a little over night.... Only because in my experiences on trucks that idle alot ive noticed ALOT more egr soot build up resulting in overloading the dpf and doc and believe it or not dirtier oil. A diesel engine was made to work and alot of people dont realize how bad it can be on them to make them "not work". But like i said these are my personal opinions take them and do what you want with them lol. I have been known to have a fu**** up way of looking at and understanding things.