Engine Hrs. vs Engine Miles ???

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harleyboy2003
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Engine Hrs. vs Engine Miles ???

Post by harleyboy2003 »

Wanting to know what the correlation if any , to compare engine hrs to miles. I know there are many brilliant minds on this forum that maybe can provide an answer. The reason I am asking is , I am looking to possibly purchase a used 2015 Ford F-150 5.0l Coyote V8 from local dealer. I suspect the truck may have previously been owned by Fire Dept. The truck is showing 8865.5 total miles on odometer and is extremely clean, but engine hrs on digital display show 1335 engine hrs and 908 engine idle hrs. So, if this truck spent most of its life idling how many miles on engine would that figure to be? Should I even consider this truck or walk away? Is idle time worse than under load time? Price is right with factory warrenty as certified pre-owned, what do you all think? I hope this was the right place to ask,
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Re: Engine Hrs. vs Engine Miles ???

Post by MadBill »

Hundreds of short-period idles from cold weather cold starts are very hard on an engine, but Fire Department units probably get heated storage and are typically idled for hours, not minutes, so I'd say it has likely led a pampered life. For ~$25, an oil analysis (if it hasn't just been changed) could be a confidence-booster.
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Re: Engine Hrs. vs Engine Miles ???

Post by Dave Koehler »

And there is always carfax to check .
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Re: Engine Hrs. vs Engine Miles ???

Post by n2xlr8n »

MadBill wrote: Tue Jul 10, 2018 1:32 pm Hundreds of short-period idles from cold weather cold starts are very hard on an engine, but Fire Department units probably get heated storage and are typically idled for hours, not minutes, so I'd say it has likely led a pampered life. For ~$25, an oil analysis (if it hasn't just been changed) could be a confidence-booster.
+1

...and maintenance from the municipality.
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Re: Engine Hrs. vs Engine Miles ???

Post by mk e »

I saw an article years ago on city taxi engine wear that talked about long periods at idle, so with low oil pressure and it was much harder on the engines than the miles would suggest. Things may have changed but that was the claim ..20 years ago? that they supported with measurements of lifters and bearings iirc.
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Re: Engine Hrs. vs Engine Miles ???

Post by Alkyfool »

Ford usually states about 33 miles equivalent for each idle hour.

My experience with Ford squads (1981 v8 to 2009 Mods) is that they could use a quart or two of oil and if no one is checking they would get to none on the stick between oil changes. Needed to use the correct oil weight and I think 5w20 is now the norm.
harleyboy2003
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Re: Engine Hrs. vs Engine Miles ???

Post by harleyboy2003 »

So if what Alkyfool is saying is correct , the engine has basically idled for almost 30000 miles! So truck has 8865.5 miles on chassis and engine roughly 30000 miles ? What do you all think? Engine seems to run great, I am just afraid of what ifs in the future and if warranty could be compromised by Ford due to engine hrs vs milage.
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Re: Engine Hrs. vs Engine Miles ???

Post by Curtis Mc »

Alkyfool wrote: Tue Jul 10, 2018 2:15 pm Ford usually states about 33 miles equivalent for each idle hour.
Doing the math myself a few times and searching the internet, I came up with 35 "equivalent miles" per idle hour, which is pretty close to your 33.
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Re: Engine Hrs. vs Engine Miles ???

Post by Belgian1979 »

I always used 2200 hours is about equal to 150000 km (+-94000 miles). Mostly used for farm type equipment.

For comparison : most generators require some sort of engine rebuild every 8000-10000 hours, so roughly equal to 350-500k km which is about right.
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Re: Engine Hrs. vs Engine Miles ???

Post by travis »

The ‘99 suburban 3/4 ton I purchased a few years ago was an ex-fire department chiefs vehicle. It didn’t have an hour meter, but it did have a lot of miles. It also had a box full of repair and mtc work receipts...I was impressed how meticulous they was on it.

Most people don’t maintain their vehicles anywhere close to enough. I know way too many people that will sell a vehicle just because it needs tires...

I wouldn’t be scared of it if the price is right. Warranty’s are usually expressed in years and miles anyway
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Re: Engine Hrs. vs Engine Miles ???

Post by hoodeng »

When i used to work on heavy plant ,our rule was 1hr =60 miles ,but that was at rated power .I see sense in the much lower figure for an idled engine.
If the vehicle is as good as you say ,buy it , first run a half load then hook up the heaviest load you can to it and find the steepest long grade you can find and give it too it [obviously all must be in order] you will probably make the thing stink like hell as it burns off it's lazy life inside and out ! but if the deal is good and the vehicle puts in you have got a great buy.

Cheers.
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Re: Engine Hrs. vs Engine Miles ???

Post by CharlieB53 »

You didn't mention what the oil pressure is.

Run it, drive it, make sure the oil is up to temp and see what the pressures are both at idle and on the road.

Chances are it will be fine. I wouldn't worry.
harleyboy2003
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Re: Engine Hrs. vs Engine Miles ???

Post by harleyboy2003 »

Thanks for everyone replies. Oil pressure at both idle and at speed look great according to gauge. Engine runs very well and no unusual noises. My main concern was any possible future issues with longevity due to the excessive idle time. If I hear no real negative responses I will probably purchase the truck. Going online I find no real issues with the 5.0 Coyote engine, so I feel pretty confident that it is a decent engine and the idle time did no harm. If anyone knows differently please let me know.
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Re: Engine Hrs. vs Engine Miles ???

Post by fastblackracing »

I have had several cars now that have avg. MPH readouts on them and they have always
read out at 30-32 mph avg. vs. run time.

So the Numbers you are seeing on the interwebs seem to be pretty close for 1 hour of
engine run time.

And being A FD vehicle with idle time and pampered lifestyle has to be better than a police
vehicle that was driven like a kid out for a joy ride its entire life. Yes?
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Re: Engine Hrs. vs Engine Miles ???

Post by cab0154 »

The coyotes are really solid engines. I would buy if it is nice and has been maintained.
"Anyone who thinks the low RPM engine will be faster just does not have as much experience as the rest of us" -The late, great Joe Sherman.
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