Most cars are parked 95% of the day. What happens when you flip that?
Posted by pineconeparty_@reddit | askcarguys | View on Reddit | 32 comments
Obviously you'll get accelerated wear and maintenance intervals, I guess my main question is do those needs scale proportionally to hours-driven? Are they less because of reduced heat cycling and time-ageing of rubber components? Are they worse because some components were engineered to take advantage of a daily "rest cycle"? What parts would wear out faster than their typical mileage-lifespan, and which ones slower?
Assume the same mix of city/highway driving as a typical car.
Downtown_Reward_6339@reddit
I theory a car driven constantly would last the most number of miles if maintained.
Back in the 60’s when 100,000 miles was considered the end of life there was an advertising bit that Mercury did with their Comets at Dayton Speedway. The goal was 100,000 miles at 100 miles an hour. 289 High Performance engines, Toploader 4 speeds and 9” rear ends. It was a walk in the park (even though 100 mph was a lot harder with no aero).
Now in real life those cars were driven to the junkyards with fatal rust (in the north) long before 100k.
Substantial_Team6751@reddit
Go research taxi cabs.
MirageGarage16@reddit
Didn’t cleetus just do this with a crown Vic? Made like 10 days straight.
FrankCostanzaJr@reddit
i saw a video the other day on youtube talking about how GM was interested on how/why so many people have been going 1M+ miles with all types of different vehicles, regardless of brand. didn't seem to matter if was hyundai, GM, honda or toyota, all these cars did 1M miles within less than 10 years.
so they did a bunch of experiments to test engine wear with radioactive bearings in the engine. they measured the oil for radioactive elements at different intervals and started/stopped some engines, while leaving others running. but i think they inferred that the same kinda of wear would happen all over the engine to all parts that need oil.
anyway, they basically found out that like 90% of engine wear happens during the first 10 or so minutes of driving, before the car is fully warmed up. and the reason ALL these 1M mile engines made it so long was because they were driven LONG distances each and every time they were started up.
so, i believe it, apparently the most damage is done to your engine (especially engines with very tight tolerances) when it's cold. they even saw less wear in warmer climates compared to colder climates...its pretty fascinating stuff.
pgregston@reddit
This is the argument for car share/self driving services. All the parking and garage space becomes available.
TheWhogg@reddit
Vehicle life is shorter by years but longer by miles. And it will give less trouble on the way there. Reduced wear specific to cold starts and heat cycles (correlated but not the same wear - heat cycles destroy plastics).
SpaceCat72@reddit
Running 95 percent of the time? I'd go to severe duty maintenance schedule. Using absolute top grade lubricants and filters. Not long interval filters either. Pore size is larger, poorer filtration.
TheWhogg@reddit
Opposite of that. What the rest of us do is severe use. Driving always hot is a holiday for the car.
Yes it should be serviced well either way. OEM or better filters, premium oil, change well before “officially” due, replace all fluids frequently etc.
Muttonboat@reddit
Cop cars never stop running for most part, I believe most cars would be fine but the maintance intervals would decrease,
SatanVapesOn666W@reddit
Those cars engines are genuinely beat to shit from all the idle hours. Things you didn't see fail on normal crown vics for example at the same miles.
smthngeneric@reddit
Not really. Atleast not crown vics. A lot of police cars were sold around 100k depending on the departments policy and then became taxis that also run all day for another 200k+ miles. Those things were tanks.
SatanVapesOn666W@reddit
They were cheap and reliable but my friends retired police cruisers always had more engine issues than my uncles towncar and our crown vic. Idle hours simply have wear, hoses get more stress from heat, oil pressure is low so give the valve train more wear, accessories like the water pump and alternator are just losing life. They were cheap to keep running, but that's different from issueless.
They were a steal before everyone tried to get them and were still $1000-$3000 for a decent one that just needs a little love. But their miles were misleading to how actual worn the engine has been. That chassis in general will run for 200k+ but youre going to have engine components failing before you expect and it got a lot of young guys in trouble/on the side of the road.
Admirable_Nobody_771@reddit
Just look at factories that have machinery that runs almost 24/7. They'd be fine, if properly maintained.
SkibidiBlender@reddit
Ask any cab company, or police fleet mechanic.
shorerider16@reddit
Those vehicles also have a much more regimented and usually better maintenance program vs private individuals who wait till something stops working to fix it.
Timmarino@reddit
Semi trucks are like this and I deal in maintenance of them. Some units run 225k miles a year and are taken out of service at 3 vs 5-6 for a normal truck. They all tend to have the same issues mile wise seals, wear components ect but the 24/7 units have less internal components wear since they never cold start or let plastic or rubber components get hot/cold as many cycles radiators, plastic valve cover ect tend to not leak as much i noticed on high use
Sweet_Baby_Cheezus@reddit
The things that you'd get more life out of would be things that are more susceptible to time (and your starter).
IMO you'd get more "driving" life out of things like serpentine belts, hoses, electrical components and paint. Most of those lose life to time as well as wear and tear, so you might get fewer issues overall if the car is constantly in use.
ChrisGear101@reddit
For engines, it is interesting. For example, diesel trucks that are driven like a daily commuter, they fall apart way faster than a diesel that drives cross country all day. It is not uncommon for OTR truckers to get a million miles on a big rig. The main reason is because they literally never shut the engine off. But if you take that same engine and drive it back and forth to work and the grocery store putting three or 4 short heat cycles on the engine every day, it may only last 200K miles. Wear and tear on other components like structure, suspension, bushings and bearing surfaces are more closely related to actual mileage.
Carstuff392@reddit
Very low RPM is also a factor. 2500 is up there for some of the big motors.
Ruins People’s Motors.
rilesmcjiles@reddit
Another factor is the size of investment in the big rig. It's common to rebuild or replace the transmission and engine a few times before the chassis is scrapped. The drive trains also go impressively long for the reasons you stated.
Running a consistent load at a consistent temperature absolutely helps the components keep going.
ZymurgyBro@reddit
I was an on call courier for 5 years. Did about 1000 miles a week in my personal vehicle. About 20-30 stops a day. Other drivers having well over 200k miles on their cars was normal. Miles wear cars but more time and heat cycles. Heat cycles are a much bigger deal then most know.
Internet-of-cruft@reddit
You have multiple factors that cause wear: Age, environment (think the air, humidity, etc.), expected load, and duty cycle.
You're talking about going from a "5% duty cycle" to "95% duty cycle".
If an average person drives 10,000 miles per year, in this scenario that car sees 190k miles per year.
All your age based components basically won't come into play so rubber will remain in shape and oil won't oxidize. Depending on start/stop cycles (is it being started up 19 times more often, or driven 19 times more?) you'll see less thermal cycling and cold starts.
If it's being driven "the same way" (not roughly accelerating, etc), then load will basically be unaffected, but wear on everything (brakes, friction surfaces, etc.) will be 19x higher.
jrileyy229@reddit
Cars don't care about rest cycles if they're working properly.
If all cars were driven on public roads 95% of the day, the entire country would be gridlock
Occams_RZR900@reddit
When I was a cop we had cars that never stopped running. When 1 shift would bring them in, the next shift would take them out.
vilius_m_lt@reddit
You mean like taxis/car service vehicles? They wear out quicker. Excessive idling is not healthy at all either. I just replaced camshaft on a 2024 car service Suburban with 60k ish on the odo with 5100+ engine hours on it which translated to roughly 165k driven miles..
drive-through@reddit
Machines perform best when they stay in service at operating temp and the rest of what we often associate with aging is often less because of how much of an effect time has on a vehicle (e.g., UV exposure). This is evidenced by how solid you’ll find pilot cars to be, if they were properly maintained. This is why “city” miles are harder than “highway” miles. I think there’s an exception when the miles go above a certain level where there’s inadequate downtime for maintenance and the operation just becomes abuse, but I think that’s obvious.
If you would like further reading on this, there are numerous studies published on OTR and taxi cabs
MiserableEducator444@reddit
driven 95% of the day instead?
engine, tire, drivetrain blowouts. very high gas consumption. alot of accidents, assuming its humans driving.
pure havoc.
pineconeparty_@reddit (OP)
More per mile-driven than the opposite example? Remember this assumes all maintenance followed to the book, based on mileage
Unique_Wolf4513@reddit
Most million mile cars have driven a ton of miles in a short time span. They get so far with servicing of course but also because cold oil is when the most damage is done. High miles on a newer car usually means it's been on and moving so oil has been warm rather than turning on and off constantly for short trips. I believe GM did a study on this to prove it as well.
Miserable-Stock-4369@reddit
Just about every part of the car would age faster than is typical. Nothing would age slower
Tony-cums@reddit
I am starting to miss the tire posts.
pineconeparty_@reddit (OP)
I don't hang out here, is this a repetitive question?