Safe to idle for 15-20 minutes at a time?

[SAP2018]

New to Diesels and bought my truck with 13 miles so I want to take great care of my dream truck.

Is it safe to let it idle with the AC on to keep wife and kids cool in the summer or is it better to shut it off and turn it back on all the time?

This is my truck

 

[Newsa]

View attachment 108362 View attachment 108363 New to Diesels and bought my truck with 13 miles so I want to take great care of my dream truck.

Is it safe to let it idle with the AC on to keep wife and kids cool in the summer or is it better to shut it off and turn it back on all the time?

This is my truck

Sometimes it is unavoidable. It isn't good for the engine and is "less bad" if you run it at high idle. I don't have a high idle function on mine because it is a manual transmission truck.

I'd say if you are driving all day in hot or warm weather, you won't do any damage because the fuel sticking to the walls of the cylinders will burn off pretty quick. If you are not driving far, you could get fuel cylinder wash and cylinder glazing which could lead to rings sticking and letting fuel leak into your oil sump.

If I'm on vacation and driving all day, I don't worry about it. Especially if you are towing.

Nice truck, by the way

 

[Deleted member 995608]

Happy wife = happy life. Keep her cool and everyone goes home safe

 

[Newsa]

Happy wife = happy life. Keep her cool and everyone goes home safe

Agreed. Unless you love your truck more than your family. Which I am still trying to figure out

 

[Deleted member 995608]

Agreed. Unless you love your truck more than your family. Which I am still trying to figure out

I hope your wife doesn't read the TDR forum

 

[Newsa]

I hope your wife doesn't read the TDR forum

Well, we actually never married. So she's just my girlfriend (of 19 years). I own the truck. Not her

 

[SAP2018]

Well, we actually never married. So she's just my girlfriend (of 19 years). I own the truck. Not her

Ha, best thing I've heard all day.

 

[nukegm]

Well, we actually never married. So she's just my girlfriend (of 19 years). I own the truck. Not her

newsa and jhawes - that little back and forth was priceless. thanks for the belly laugh. so true! cheers comrades!

 

[AMink]

Well, we actually never married. So she's just my girlfriend (of 19 years). I own the truck. Not her

Whatever helps you sleep at night.

 

[Newsa]

We're still kicking each other's tires.... So to say.

 

[Deleted member 995608]

Well Newsa, some of the happiest couples I know never married or had children

 

[sag2]

OK, to answer the original question, you can idle the new trucks all day without huring anything.

 

[Newsa]

OK, to answer the original question, you can idle the new trucks all day without huring anything.

Ok, thanks. I was trying to minimize idling because of Cummins recommending no more than 5 mins at a time.

I guess that short trips (grocery getting) doesn't hurt it either?

 

[KATOOM]

Its my truck, my fuel, my money... I'll idle all day and night if I want.
That said, I know Cummins has their 5 minute rule (and have had it for a long long time) but I have yet to hear of anyone talk about problems from extended idling on any truck. I sometimes wonder if the EPA forced Cummins to include that statement in their manual.

 

[kthaxton]

Its my truck, my fuel, my money... I'll idle all day and night if I want.

Unless of course....you live in an area that prohibits such a thing.

 

[Tuesdak]

Any "bus drivers" on here? What is the first thing the bus driver does if the bus is going to be at a stop awhile? Maybe second after parking brake and doors open. A: turn the high idle on. This gives the AC compressor more RPM and more importantly more fan RPM to lock up properly and move air. I suggest it helps the DPF and other emmisions too.

The start/stop causing more wear debate goes on. UPS drivers have the engine off before the truck stops rolling...

Clearly if you want to idle it use high idle. It's easier to keep a truck cool than cool it down from 170 degrees cab temp and over. Just add fuel...

 

[sag2]

I suppose I should have added a couple things.
In very cold ambients prolonged idle is not good if operating temperature cannot be maintained. Cold weather fronts and high idle recommended.
In hot weather high idle helps the A/C operate better. At idle there should be little to no NOx emissions so DEF is out of the picture. I'm sure the 5 minute rule is for emissions only. The fuel systems are so good now, soot is hardly a concern.

 

[Tuesdak]

Would high idle help if DPF is in Regen?

 

[sag2]

Would high idle help if DPF is in Regen?

If the system is in regen, the ECM will do what it has to in order to complete the regen. If it can't, it just suspends it until conditions can be met.

 

[Hippy43]

I've been asking this same question for almost 2 1/2 years now with no real set answer. I'll leave mine running, high idle, when I have to leave someone in the truck when I go into the store. Usually no more than 15 - 20 minutes.
Mechanics I know tell me "You see semi's setting all night running". Nephew's company has a new fleet (16's - 17's) doing oil field service and they pretty much stay running all day.
Construction company working on our building for the past two years left their new RAM's running pretty much all day in the summer time.
Maybe it's time to call Cummins and play "Ask an Engineer" and see what they say... (LOL)