If you are a forum AO (**** owner) and think nothing of idling long periods (10+ MINS) once you are in the know, you will want to turn your engine off. In addition to the wet stacking readings all over the web, As Tom stated, the big truck manuals recommend shutting engine off Cummins for example does NOT recommend excessive idling of the engines, since it can cause excessive carbon buildup on the pistons, piston rings, injector tips, valves, etc. From In.gov: Letting an engine idle actually does more damage to the engine than starting and stopping. Running an engine at low speed (idling) causes twice the wear on internal parts compared to driving at regular highway speeds, which can increase maintenance costs and shorten the life of the engine. I am **** about my new truck and want it to last a long time. Extended Idling hurts your engine. This is a fact, not an opinion. Not idling is in my list of things I do for long engine life.

No idling longer than 3 mins.
Change the oil early
Regularly drain the DFCM
Add Lubricity Additive
Proper Air the tires
Allow engine 3 min warm up before driving
Allow engine 3 min cool down after heavy long pull
Coolant test before it is needed

You have to either care about your engine, or care about your grandmother who is sitting in the hot truck. "Granny, roll down the windows and i'll be right back!" You can't disagree that it is not good for your engine which is what the OP was trying to bring raise for discussion.

 

That being said, install the seic mod with a 20k ohm resistor and if u wanna let her run just flip the switch and be worry free. Anything over 1000rpm isnt considered idle..

 

But it counts as idle time in the computer.

 

Not over 1000

 

Not even sure high idle is good, but better than slow idler. The GOOD news is that 6.7 owners dont have to feel guilty (not that we would anyway) about polluting the air from idling since our trucks convert the nasty stuff that kills and causes cancer, to the good stuff needed to sustain life.

 

How do you know this?

 

Experience

 

The computer considers well over 1000 RPM to be idle. I have 25% It has to be under 1500 that is idle. Educated guess but moving down the road under 1500 RPM and 25 MPH must be idle or my truck is all screwed up.....
Im 1/4 mile from the limited access highway..... I dont idle that much, not that anyone would believe me but I dont.....

 

i dont have a clue....

but would think that the easiest way for Ford to calculate idle is any time the engine is running with no throttle pedal input. So you could be going 70mph down the interstate and let off the accelerator to coast down a hill and be considered at idle?

I dont know just thinking out loud....

 

to the op's question...
better for who or what ?!?

ME or my passengers in 100 degree Texus heat - that baby is idling...

heard all the stories about coking and wet stacking etc... note that most of those articles where written YEARS ago ?!? things have changed a bit...
this is my fourth ford diesel - 4 of them had remote starts - 4 of them went many miles with lots of ilding...

to each his own, but the truck is not my pride and joy, it's just an appliance....
oh, and it belongs to me not the other way around

 

Interpret this how you wish, but I found this on Ford/Motorcrafts' site. It could potentially be the answer to the idle hours and how it counts idle time.

*Sustained heavy traffic less then 25 MPH or 40 KMH. (One hour of idle time, is equal to approximately 25 miles or 40 km of driving.)

I read that and think anything less than 25 mph is calculated as "Idle Hours."

 

I have high idle hours and use my 1,400 RPM SEIC when I do idle (hooking up trailer, etc.) so it must count.

Throttle input is one option
If you have the fuel usage PID showing on the CTS, the fuel usage goes to 0.00 when coasting at any speed.
You would think Ford would have factored speed in to the computer calculations though.

 

Cats ruin my quality of life. Have had no effects from the diesel. I can idle my 7.3 for days on end and drive off like nothing ever happened (300,000 miles and counting). What hurts the 6.7, as far as idling is concerned, is the EGR, DPF and SCR BS. Remove all of that crap and you end up with a happy engine which, like the old 7.3, can idle all day long. With the emissions throttling equipment you better have the high idle mod.

Tux Scorpion: Don't post misleading information like "Not over 1000 and experience" if you don't have hard data to back it up. Seems to be a mystery on how Ford calculates cumulated idle time. Maybe it was tounge in cheek but I didn't interpret that way.

 

Even high idle produces a ton of soot on these stock 6.7L.
You can see the soot GPL creap up several numbers in 10-15 minutes.
Just have to remember to blow that crap out.

 

Would like to see a comparison of soot production on a low fuel pressure injection system like the 7.3 compared to a high pressure injection system like the newer CR diesels. I am sure CR systems produce a lot less since all the manufacturers have gone to HP CR injection systems to meet EPA mandated emission levels (with exhaust aftertreatment of course). So, the 7.3 probably produces a lot more crap than the choked up 6.7 yet doesn't seem to suffer any ill effects in doing so (other than killing trees and causing earthquakes and cancer in Kalifornia).