Idling the truck for extended periods

Hey all, as a superintendent in residential construction it’s inevitable that I’m in my truck for much of the day driving the subdivision and getting in and out to check houses, make calls and work on my tablet. Often times the truck is idling with the AC or heater on. I’ve read this isn’t good for the engine but it’s pretty unavoidable. Is there anything I can do to offset the negatives? Change the oil more frequently or use an additive? Thanks in advance for any help.

 

I'll be interested in the experts answers here also...

I've always heard it's bad for gas motors, diesels are fine for idle....bit I've never heard WHY...

And does being in drive, but food on brake at idle matter...as in someone who lives in Los Angeles or DC or other heavy traffic areas, do their cars die faster?

 

I’ve always been told that if you’re idling for extended periods and / or in stop and go traffic frequently that you should go by engine hours and not miles for oil changes . For example : if you’re travelling at 60 mph it would take approximately 166 hours to reach 10,000 miles so you should look at changing your oil at around 166 hours of running time give or take .

 

That’s good to know. Thanks.

 

In my old job we had tahoes that would idle all day, sometimes well over 8 hours a day. We only did basic maintenance and oil changes at 5k. The engines never broke down. We’d keep them to anywhere between 36k to 60k before getting new truck. I’m sure it will damage longevity though beyond that. I’d never buy one of those trucks used.

 

Go by hrs, not miles for oil changes. I managed a fleet of 160 units and 60 of them were trucks of all makes that ran/idled for 24 hrs a day 7 days a week 4-6 months out of the year. It doesn't hurt them any more than driving does.

 

Install a engine hours meter, like the gradall

 

The army idles HMMWVs and other vehicles for days, especially when it’s cold out. They use the jp-8, which I think is diesel.

I know that’s probably different than commercial diesel vehicles in build and usage though.

 

All commercial equipment have hours meter, that’s how the equipment rental company keep track of maintenance.

 

The department that I worked for was poor, We hot seated Ford 4.6 liter motors for months, I don't even think those those motors ever got shut off! Lol, They were turned into auction at 200k..

 

I always wonder why no one ever shuts them off when filling up....like it seems like a requirement to have your f250 running while filling up.

Also I know that that it really inst that good to let it idle in the winter time to let it "warm up". Another thing transfering over from the carb days... Modern engines do not need to warm up and its best to just get in the and drive them, especially diesel since they take forever to warm up at idle.

...as I see that it is all mentioned in the link you posted. Very informative.

 

Change oil after 80 hrs of your idle and drive time combined. Don't forget your drivebelt, plugs, etc. will be due for replacement probably about 30% less than the recommendation on the mileage. So if plugs are due at 100,000 you should be changing them about 70,000.

 

This is something I’ve always like about small engines. Most dirt bike/lawnmower/boat motors go by hours which makes sense to me. Because as you eluded to someone who does a lot of city driving might only hit 2k miles in 150 hours but someone who does a majority of highway driving might hit 10k miles in 150 hours. Either way I think as long as your in a consistent oil change interval then you’ll be fine.

 

I wonder how the fuel injectors play into this paradigm and if using lower octane, more additive filled gas plays into the idling as described?

 

Ideally you'd measure by engine cycles with a load based factor, but hours is close enough. Miles is a convenience thing adopted by the passenger car market, why people say "all highway miles" means high miles = low hours. The manufacturer usually has asterisks for odd duty cycles like idling or towing heavy cases to reduce maintenance intervals from the typical grocery getter.

 

Good move. I’ve read a lot that the 7.3 gasser is a good substitute for a diesel. Certainly not the same power and torque, but also not the cost and maintenance of a diesel. I’d be curious what your friend thinks of the “Godzilla” motor.

 

Just change oil a little more often. Idling is about the lowest stress an engine sees. Shouldn’t affect longevity too much as long as it’s maintained well. I’d also verify often that the cooling system is full with no leaks and the fan clutch is in good working order.

 

A buddy used to work in the maintenance yard for the state, trucks used to come in complaining of rough idle because of them sitting at the jobsites with the a/c blasting all day.

They had cabinets full of Berrymans B12 Chemtool and would put a bottle in the tank and go out and beat the hell out of the truck and get it good and warm....this was back in 2005 so ymmv.

 

I'm not sure if it has been mentioned yet but I believe it says in the manual for our 1st gens that it's bad for the cat's to idle longer than 15 minutes.

 

I’d worry more about heat buildup than changing the oil.

 

How long do you think Cop cars idle?? Besides driving them all day long, they sit in many places filling out reports, etc. Taxi companies typically try to buy them up after, and drive them some more. Pretty sure regular oil changes will keep them going.

 

The automatic high idle feature on a diesel was implemented to prevent wet stacking in the cylinders when operating in cold temperatures. Wet stacking is no longer an issue due to the use of grid heaters throughout the industry. The other reason for the high idle feature on a diesel engine is to run items such as a PTO. The modern diesels come with a circuit that you can actually wire a potentiometer into to vary the idle dependent on what is needed.

On a side note, I don't know who that guy is on that website but he sure as shit is not a diesel mechanic. I owned diesels for over twenty years and I can pick apart most of what he listed.

 

I'm no expert, but I can chime in with my high mileage 5.7 has done long idles while I do store runs and other errands over the 15 years that I've owned it... my eldest is special needs and it's a gamble the times I'm able to take him in a store, so usually.. he stays with mom in the truck at idle with the AC or heat on..... I've only followed routine maintenance and haven't followed hourly maintenance periods, nor logged any... engine has no issues with the exception of not liking summer heat anymore, lol..... it is said idling can age an engine to twice the amount of miles... this guy breaks it down on a newer Chevy Caprice PPV engine.

Edit: 14 years, my bad it's an 07.. lol
https://youtu.be/XBAoaBj7trI

 

One of the best things a person in this situation could do is to swap the fan over to dual electric fans for maximum cooling. Kinda a bit of work though and I would probably use geographic location as a guide to determine the benefits.

 

My work 2018 Tahoe with the 5.3 runs for up to 16 hours some times, has about 55k miles on it, i just take it to fleet for basic / routine maintenance and it hasn't had any issues.

 

I used to idle my Titan for about an hour every work day, on top of the driving. After the warranty expired I started doing oil changes at 10k miles with high quality synthetics (Royal Purple or Mobil1) and a Purolator high end oil filter. I sold it at 235k miles to a coworker, who is still driving it at 250k+.