Annnnnnd I let it idle

[AlbertaClipper]

Sometimes I feel like I shouldn't own a car/truck. Or anything nice.

So my kiddo (6yr old) LOVES airplanes. We drove by the airport today and saw one take off up close from the busy road, and she got so excited - it was awesome actually. Well, I pulled off so we could watch more, and when she got her seatbelt undone, she kicked over her milk bottle. I went around to help her out and do a quick clean up and we went into the back of the truck to watch. She LOVED it.

In the mayhem as I parked, I forgot to shut off the engine bc I went after the milk.

NEVER heard the engine running because we were on a very noisy/busy road and, well, you know, airplanes.

That thing idled for 40min.

After all the threads, and the excerpt in the manual...think I did anything bad? Overall, I have low idle hours. 6800 miles on the truck. The oil was just changed 700 miles ago.

 

[jgreene]

Your truck will be just fine. Idling won't do it harm. Especially for 40 minutes. The big thing is the water build up in the exhaust that you wouldn't want sitting there. But a short drive gets rid of it.

 

[piening2150]

You're fine. Why would less than an hour of idle hurt anything? Many police cars have the same 5.7 Hemi and idle for hours on end, every shift, for their whole service life.

 

[Richard320]

You wrecked it. Trade it in quick before it falls to pieces.

Seriously, it must be nice to have such worries. Anyone who lives in LA County or environs could get stuck idling longer than that -- in gear, with the AC blasting! -- on any freeway on any day, for no apparent reason. Yet the trucks survive.

 

[Cajun_]

Truck is ruined. Completely totaled. I'll give you $5000 for it.

Sent from my SM-G998U1 using Tapatalk

 

[HSKR R/T]

You're fine. Why would less than an hour of idle hurt anything? Many police cars have the same 5.7 Hemi and idle for hours on end, every shift, for their whole service life.

And many police cruisers have issues with cam and lifter failures.

 

[HSKR R/T]

Your truck will be just fine. Idling won't do it harm. Especially for 40 minutes. The big thing is the water build up in the exhaust that you wouldn't want sitting there. But a short drive gets rid of it.

The problem with long idle periods is the engine oiling sucks on the Hemi at idle. Needs higher RPMs to "splash" oil up to the cam/lifter area.

More than likely he will be fine, but it's not recommended to sit at idle for long periods of time

 

[AlbertaClipper]

The problem with long idle periods is the engine oiling sucks on the Hemi at idle. Needs higher RPMs to "splash" oil up to the cam/lifter area.

More than likely he will be fine, but it's not recommended to sit at idle for long periods of time

Which is the reason for the post... I mean, it says it in the manual -- don't let it idle for long periods. I don't think I destroyed the engine, but at the same time, it kinda sucks to know you made a mistake.

 

[Idahoktm]

Which is the reason for the post... I mean, it says it in the manual -- don't let it idle for long periods. I don't think I destroyed the engine, but at the same time, it kinda sucks to know you made a mistake.

I just searched the entire manual for a caution about prolonged idling and there is no such warning. There is only a warning about idling as it pertains to the ridiculous California P65 nonsense.

 

[Richard320]

I just searched the entire manual for a caution about prolonged idling and there is no such warning. There is only a warning about idling as it pertains to the ridiculous California P65 nonsense.

 

[AlbertaClipper]

I just searched the entire manual for a caution about prolonged idling and there is no such warning. There is only a warning about idling as it pertains to the ridiculous California P65 nonsense.

2021 manual page 136

"Engine Idling - Avoid prolonged idling, long periods of idling may be harmful to your engine because combustion chamber temps can drop so low that the fuel may not burn completely. Incomplete combustion allows carbon and varnish to form on piston rings, cylinder head valves, and injector nozzles. Also, the unburned fuel can enter the crankcase, diluting the oil and causing rapid wear to the engine."

And again, add the poor oiling at idle theory with regards to lifters/camshaft failures...

 

[UnloosedChewtoy]

2021 manual page 136

"Engine Idling - Avoid prolonged idling, long periods of idling may be harmful to your engine because combustion chamber temps can drop so low that the fuel may not burn completely. Incomplete combustion allows carbon and varnish to form on piston rings, cylinder head valves, and injector nozzles. Also, the unburned fuel can enter the crankcase, diluting the oil and causing rapid wear to the engine."

And again, add the poor oiling at idle theory with regards to lifters/camshaft failures...

Unless you're noticing issues, I'd just move on. You made a tiny mistake, but 40 minutes is nothing, as others states. I think you're just being paranoid and worrying over nothing. (No offense intended, I do this myself with my truck to.)

Yes, prolonged idle for hours upon hours over its lifetime may cause issues. However, 40 minutes is a far cry from what many others do. My wife let her Hemi in her 2014 Grand Cherokee idle for 10-15 minutes every morning and evening (before leaving for work and before coming home) in the winters here, sometimes 20+ each way on really cold days in December/January/February, for most of the 6 years we had it. She gets cold easily and really wants that heat.

Never had any issues with the engine, and it was an Enterprise rental for 1 year before we bought it. Put over 50k on it over those 6 years. Traded it in last year for a 2018 Grand Cherokee Trailhawk, again with the Hemi, and I doubt she is going to change her ways.

 

[Idahoktm]

2021 manual page 136

"Engine Idling - Avoid prolonged idling, long periods of idling may be harmful to your engine because combustion chamber temps can drop so low that the fuel may not burn completely. Incomplete combustion allows carbon and varnish to form on piston rings, cylinder head valves, and injector nozzles. Also, the unburned fuel can enter the crankcase, diluting the oil and causing rapid wear to the engine."

And again, add the poor oiling at idle theory with regards to lifters/camshaft failures...

That's regarding the diesel engine, not the Hemi.

 

[theblet]

I got stuck on the interstate because of a wreck and idled for like 3 hours. I’m sure I’m not the only one this has happened to. You’re good!

 

[JC4041]

You wrecked it. Trade it in quick before it falls to pieces.

Seriously, it must be nice to have such worries. Anyone who lives in LA County or environs could get stuck idling longer than that -- in gear, with the AC blasting! -- on any freeway on any day, for no apparent reason. Yet the trucks survive.

I hate having to go to the VA down in Sepulveda or the West LA VA.....where the 5 and 405 meet SUUUUUCCCCKKKKKSSSS. I try to set my appointments during "no rush hour", but it never fails to have some sort of traffic jam for no damn reason.....

 

[Andymax]

In the grand scheme of automotive "mistakes" this one ranks way down on the list. I idle my truck all the time...Our last hemi same idling profile, went 254K miles zero issues.

 

[silver billet]

There is no proof that idling causes lifter failures, just speculation based on the amount of cop cars with lifter failures so people start jumping to conclusions and think that cop cars = iding = failure. There is also no proof that idling doesn't cause failures, but there are other theories; cars that idle extensively are required to use the "extreme duty" maintenance cycle which is changing the oil at 320 hours. If a cop car runs 24/7, that means it should be getting oil changed every 2 weeks. If it runs half a day it needs to change every month. Many police depts don't follow that schedule, so the bad/dirty oil starts to form deposits on the needle bearings of the lifters and they sieze up, eventually the lifter takes out the cam lobe and its game over.

There are Rams that have over 1000 idle hours with no lifter failure (see "high mileage edition" in the "truck central" youtube channel), and some that fail with < 20,000 miles.

The lifters are primarily lubricated via pressurized oil galleys, not crank splash. This design has not changed since 2003 when the hemi was re-introduced, so if we needed to depend on crank splash for lifter lube then the pre 2009 hemis would be having lifter failures as well, which they don't; therefore it's not a crank/splash problem.

We have also seen an analysis of failed lifters/cams from a metallurgy specialist and he basically said that oil was present, but was not effective ("insufficient lubriscosity" IIRC).

Basically the best prevention is: change your oil frequently (< 8000 miles), use 100% synthetic, and if you're really into it (but ok with voiding warranty) run something like Redline 5w-30.

Another theory; the hemi's were originally designed for 5w-30, but dropped to 5w-20 to improve fuel efficiency. Nothing in the design changed when they dropped the oil weight, and the manual for a period of time even still "allowed" you to run the 30 weight. This theory says that the 20 is too thin and that would be partially backed up by the specialist report mentioned above.

 

[SD Rebel]

There is concern of not idling too long because of the oil splash thing, not getting enough upper end lubrication due to the engine design. But they have these engines in police and work vehicles that may idle for hours daily, with no special consideration compared to civilian versions in terms of idle lubrication.

40 minutes is barely more than your average day being stuck in congested traffic in any busy city in the US. Heck, I spent literally 25 minutes yesterday in an In N Out drive thru line waiting for a couple of burgers and fries. Almost all of that idling with zero throttle since I'm just letting off the brake to creep forward in line.

 

[CaptainCJ35]

The problem with long idle periods is the engine oiling sucks on the Hemi at idle. Needs higher RPMs to "splash" oil up to the cam/lifter area.

More than likely he will be fine, but it's not recommended to sit at idle for long periods of time

Idling for 40 minutes... once... is different than idling for hours a day, weeks on end, with infrequent oil changes

 

[GKIII]

40 minutes of idling isn't going to hurt you...