Or for that matter pretty much only driven for short trips?
The logic I’ve heard is that longer trips and highway speeds get the condensation out of the fluids and that an engine not running hot enough will cause faster degradation of the parts as a result. Is it true or just what people say? Please not just IMHOs.
According to one of my grandfathers, who was a mechanic and ran his own garage for many years, not running a car long enough to get everything good and hot would eventually cause the exhaust system to rust out due to condensation. That was 30 or so years ago, though, when American cars seemed designed to corrode as quickly as possible. Exhaust systems today are made from rust-resistant alloys, so I don’t know if it is still a major concern.
I’ve heard tell of the practice of taking a car out and flooring it on the highway being called an <ethnic> tuneup, so the idea that pushing a car hard for a bit can be good for it has been circulating in pop culture.
In practice and per mile, yes. Freeway driving is very easy on brakes and transmission per mile. Urban stop/start driving is hard on brakes and transmission. Compare say two cars, both with 50,000 miles on the clock, one owned by a guy who lives in the country and drives 20 miles each way on open roads to get to town, and one owned by a guy who lives in an urban environment and drives in heavy urban traffic averaging say 3 miles each trip. The former car will have much less wear in many components. Once the former guy has got onto the open road he may barely touch the brakes or change gear for tens of miles. The latter guy is probably going through the gears and braking every few hundred yards.
That makes sense but I don’t see how it answers the OP. Suppose that you drive only 3000 miles a year, mostly just up to the supermarket or the like. Does it actually do the car good to take it on the highway for a few dozen miles of high speed? What about a lower but steady speed? My car is five and a half years old and only recently passed the 20,000 km mark. However nearly half that mileage (kilometrage?) has been done on trips of 100-400 miles.
There’s nothing magical about highway speeds, you just need to get the car up to normal operating temperature. For most cars with a water temp “gauge,” that means the needle is halfway between hot and cold. 5 minutes of driving will do the trick, and there’s no reason to go any particular speed.
Getting the car up to that operating temperature makes sure the thermostat opens, which routes coolant through the radiator and hoses. The oil will get to the right viscosity (cold oil doesn’t flow well, nor does it lubricate well.) Since oil is used both to lubricate the engine and to remove contaminants, it’s important that the oil gets warm enough to do both jobs. The same is true for the transmission and/or differential lubrications. Lastly, getting the engine hot will blow out any condensation in the exhaust. It’s true that exhausts are better than they were, but they’re still metal, and metal doesn’t like standing water.
For most people with a normal 5-10 minute commute, none of this is a problem. It becomes an issue for cars that are only used to drive 45 seconds to church on Sunday, and maybe 90 seconds to the A&P. If the car is never brought up to temp, the engine can wear prematurely, the exhaust will rust out faster, and all of the hoses are likely to get brittle. Car collectors are encouraged to take their cars on a longish trip every few months to get everything hot and shake out the kinks.
As a final note, I’m a big fan of the Italian tunep, although I’m not sure it actually does anything for fuel injected cars. In my mind, the extra fuel cleans the valves (which is plausible) and the injectors (maybe), and cars seem to run better once you’ve wrung them out a bit. But it may all be in my head.
Decades ago, engines would typically build up carbon deposits in the combustion chambers if they were only run at lower speeds. The deposits negatively affect performance. Some vigorous driving at highway speeds (see the Italian tune-up in steronz’s link) could prevent and/or cure this condition.
Nowadays we have computer-controlled ignition and fuel systems, and most gasoline has detergents, making this problem much less common. Modern engines are unlikely to suffer from a lack of highway driving, so long as they get fully warmed up often enough.
Operating time matters more than mileage. Back when I worked at Ford SciLab, they figured that average speed was 50. Prior to the late 70’s, engine parts were designed for 2K operating hours, to give a 100K part lifetime. Of course, if they’re all designed to go 100K, some are going to break early, so there was a big emphasis on changing that mentality. I’ve put over 150K miles on every (American) car I’ve owned since my 82 Escort (which died horribly at 100K). Most of my driving is commuter with 20-30 minute one-way trips, which isn’t hard mileage.
My wife had a two hour all-freeway round trip commute, and her Chrysler Sebring was over 190K when she traded it in, and it was still running very well. But I bet I had more operating time on my car.
The worst is indeed frequent short trips where the engine doesn’t get time to warm up. Sorry, I don’t have a cite, but this is pretty common knowledge. (Please feel free to fight my ignorance if anyone knows otherwise and can back it up.)
However, with modern (post 1970) oils, this isn’t nearly as bad as it used to be. SAE-30 oil doesn’t flow well until the engine is warm, so when running cold, you’re running with insufficient lubrication. Newer SAE 10W30 or better oils flow reasonably when the engine is cold, offsetting this issue dramatically. But still, parts wear differently at different temperatures, so you’re best off running the car most of the time at a constant (warmed up) temperature. And before your engine is warm, GO EASY! Avoid quick starts, and take it slow up any inclines.
Another issue is carbon buildup. I don’t know whether this even happens with modern control systems and emission controls – cars really are quite different today than they were in the 70’s. Anyway, with the older cars, running most of the time with low loads (not pushing the engine) could cause carbon deposits on the cylinder walls. These would continue to glow after killing the ignition, and you’d have a car that would keep running (kinda) after shutting it off. The quick fix was to run the engine hot for a good bit, like taking a freeway joy ride.
Yes, that did happen, and it did work. But that was back in the days of carbueretors, no emission controls, and big-block engines. These days, most cars are not overpowered, so even mild city driving should keep them loaded well enough (sorry, this is just MHO part you asked not to get). In any case, it’s been a LONG time since I’ve heard a car keep running after it was shut off. I’m not sure whether that’s because of no carbon buildup, or better fuel control (no carb bowl fulla fuel to draw, to keep the engine sputtering).
The Car Talk guys say that the best way to get a car to last long is to go easy on acceleration and breaking. They didn’t back that up with much explanation, but it sounds right to me, and it seems to work pretty well for me, too. I think we’ve had 8 cars that we got over 150K miles and were still running well (but starting to need more frequent repairs) when we replaced them. Usually, it’s the transmission that starts to go at that age. This included Ford and Chrysler cars. I have nothing against GM, I just got employee or family discounts on the other two makes.
There sort-of is, it is almost ideal operating conditions for a car. Relatively low but variable loads, great airflow for cooling, in general lower range for RPM’s, stable voltage/ample electrical power produced (no voltage sag when using a lot of accessories when running at highway speeds). Plus the car doesn’t ‘age’ as much per mile as it would in stop and go driving.
You need to get the oil in both the engine and transmission up to operating temp, this is very important, and that takes longer than the coolant.
Also from experience car that are driven only in short trips will rot out the exhaust in a very short time, while cars that are driven long distances will last about 3X as long.
Another boring thing to mention: there are many diesel cars, something that you don’t really have the other side of the pond, especially so-called “performance” diesels (oxymoron if ever there was one) that if not driven at reasonably high speed regularly their particulate filter will clog.
I do not understand why anyone buys a three litre jag to drive around town but they do: Motorist is told his £45,000 Jaguar keeps breaking down because he is not driving FAST enough | Daily Mail Online
So what of the trope about the little old lady from Pasadena who only drove to church on Sundays?
It’s obviously only a joke, but there was no basis for it? Did it have things completely backwards?
When I lived in Roanoke VA, the manager of a local Midas Muffler shop told me his shop was one of the top performing Midas franchises in the country. Supposedly because Roanoke was (a) big enough to support a Midas Muffler shop, and (b) small enough that most commutes were 10-20 minutes.
The condensation in the exhaust system would never get completely burned out, leading to premature failure.
Anecdotal, so there you go.
My dad was a salesman in the upper Great Plains and drove over 60,000 miles per year. Almost all (>95%) at 55+ mph. I used to change his oil every 15,000 miles (after the first 20,000 miles and it would come out still brown and occasionally still see through. Had had transmission problems at 270,000 miles on one of his cars (a Saab 900) and they replaced the transmission and pulled out the clutch. The clutch was maybe 10% worn as were the brake pads. The only thing that the car “consumed” was fuel and tires as those were on the normal schedule of wear.
So I absolutely agree that driving conditions determine car life more than simply time.
Another thing is that some small-displacement turbocharged cars have a sludging problem, which can be mitigated if the oil is usually brought up to operating temperature. I’m thinking of the 2000s VW 4-cylinder Passats.
So how will these factors play out with plug-in hybrids? If I generally drive most of my miles on electricity only and only occasionally engage the ICE, and then for fairly short periods of time (essentially acting like a little old lady driving to church on Sundays), will my ICE last many years (being used for perhaps only 3 to 5K miles a year) or will its lack of regular use cause issues itself?
(For their part GM advises oil changes every 2 years on the Volt and Ford’s Energi system allegedly monitors oil quality informing you when a change is needed but states no longer than 2 years.)
With a plug-in, the ICE won’t be used at all until the battery is depleted, at which point it behaves like a regular hybrid. If the ICE is needed, the computer will leave it on until it warms up. That’s part of why the Prius takes a big mileage hit in cold weather-- EV-only creep mode and start-stop at lights are disabled until the engine fully warms up.
It could be an issue if you have a commute that’s just barely beyond the EV-only range of a Volt-type plug in, so you regularly turn the car off right after the ICE engine comes on. Otherwise, though, a plug-in hybrid should hold up far better with short trips than a conventional car.
Early 2000s VW 1.8T engines had a sludging problem because it was a poorly designed piece of shit. No other small displacement turbocharged engine has this problem, although a few other engines, notably the 2.7l Chrysler V6 and some early 2000s Toyota V6 (IIRC) also had this problem for similar reasons (bad design of the oil/cooling channels, leakage of coolant into the oil, or oil specifications that were either incorrect or ignored).
A turbocharged engine will certainly start having problems sooner if there is a sludge problems, as the rotating assembly of the turbo is cooled by oil flowing through thin oil lines.
It’s important not just to get the oil to full operating temp, but to actually hold it there for a little while. During a cold start, nasty stuff (raw fuel and excessive amounts of combustion products, including water) slips by the ill-fitting cold piston rings and ends up in the crankcase, and that stuff doesn’t just suddenly disappear; it takes time to boil it out of the oil and drive it out of the crankcase vent. Once the engine is warmed up and the piston/rings/bore are all sealing nicely, blow-by is minimal, especially if the average load on the engine is low (e.g. a gentle cruise to church, as opposed to a 70-MPH highway cruise).
Car owner’s manuals typically say to change the oil more often depending on your driving habits: if you do a lot of short drives, chances are you rarely warm the engine up to full temp and dry out the oil properly, and the oil additives that are supposed to deal with corrosive combustion byproducts are being used up more quickly.
I’d say the secret of long engine life is for the engine to run continuously-start/stop episodes shorten the life. NYC taxicabs run over 300,000 miles-and they stay running most of the time. This means that the oil stays hot, and blowby vapors and water vapors never condense into the oil. My Dad was a local salesman-he was always starting and stopping…and his cars were shot by 90,000 miles. I have seen cars driven on the highways (only) that were like new at 150,000 miles.