Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Any truth to the notion that a car is conditioned to a certain type of driving?


My husband and I are considering buying my parents’ 2005 Prius because they want to trade it in and it would be a cheap way to get a low-mileage hybrid that we know the history of. We’ve already done the math and realize that it probably won’t be a money-saver for us, but that’s OK; it’s more about reducing our carbon footprint than saving money.

My question is this: the car has about 35K miles on it, mostly short trips around town. I would be using it for my daily commute-- about 60 miles a day, mostly highway. Is there any reason to worry that it’s not “used to” highway driving? I’ve heard that a car can be “broken in” to a certain type of driving (i.e. town)and then not be optimal for other types (i.e. highway), but my source for that info is suspect. :wink:

Any thoughts?



My old Oldsmobile that I purchased new in 1978 heads immediately to my favorite bar and I don’t have to even touch the steering wheel. The car has learned this route and it is reluctant to go anyplace else. Fortunately, the bar now has wi-fi, so I can give useless answers to questions on this board.

What you have heard is bogus. Back in the old carburetor days, engines used to “load up” with carbon deposits. A car that only traveled around town might need to have the cylinder head removed for a valve and carbon job in severe cases. Most of the time we could take the cars out on the highway for a little run and all would be fine.

The Prius from your parents should be fine. Although the Prius system with the regenerative braking is really at is maximum potential in town driving, the Prius does obtain good mileage on the road. A friend of mine has a Prius and his wife made a 55 mile commute with the car. The Prius would make more sense for me in my daily commute across town to the bar, but my Oldsmobile already knows the route, and I don’t want to spend 10 years teaching a Prius this path.

Yes, the source of your information is very suspect indeed. There is NO TRUTH to this whatsoever.

The Prius gets its best mileage in city driving, but that doesn’t mean you can’t use it for a highway commute. I see Priuses all the time doing 75 mph, or more, on the PA Turnpike.

As with any vehicle, follow the maintenance schedule that’s included with the owner’s manual and the car will last a long time. The Prius has an excellent reputation for reliability, and getting a car with a known history is a big plus.

Enjoy your Prius.

I vote this as “best post of the day.”

I actually had a high school auto shop teacher from the 60’s that advised to take your car out on the freeway and “blow out the carbon” occasionaly. There are other things that this man taught me that I still value today but I don’t take my 2004 F-150 out to “blow out the carbon”.

The advice on your Prius,forget it. It is good you see your Prius excels in city driving but has many lower priced competitors in the highway driving field.

Yes, there is some truth to it. An internal combustion engine has pistons with rings. These rings wear down the cylinder walls where they travel. Over a long period, the cylinders develop a ridge at the extent of the ring travel. The faster the engine turns, the farther the piston/rings travel in the cylinder bore. So if an engine spends most of its life running at low rpms under light loads, then the ridge that develops occurs at the maximum point of the piston/ring travel for that engine rpm. Now someone comes along and revs the engine way past the “normal” rpm that the engine has experienced and the rings impact this ridge and may be damaged.

The wear ridges take a long time to develop and in order for them to be a problem, the next user must be revving the engine well past the prior owners usage patterns. On a 35k mile, modern engine, this is not going to be a concern. Especially one used infrequently in a hybrid that has been driven in the way it was intended to be used. No need to worry at all IMO.

The stroke of a engine is not dependant upon engine RPM. The pistons travel the exact same path no matter what the engine RPM.

My dad bought a 1954 Buick in 1955, the year I started high school. He would pour an can of Casite in the gasoline tank, drive it around for a while and then take it out on the highway. He would put the car in second gear (it was a manual transmission) and run it up to 65-70 mph in second gear. The car would leave a quite a smoke screen of black smoke. When the car quit spewing black smoke, he would shift it into high gear. I thought this was hard on the car. However, when I bought the car from him in 1963, it started running poorly. I took it to the Buick dealer and an old mechanic said, “You don’t need a tune-up. Pour a can of Casite motor tune-up in the gas tank, take it out on the highway and run it up to 70 in second gear”. I took his advice and the car ran fine. It had 120,000 miles on it at the time. I’ve used the same treatment on my 1978 Oldsmobile when it would ping on acceleration. I would take it on the Interstate and hit the accelerator downshifting the transmission. This always cured the pre-ignition problem. Of course, the Buick and the Oldsmobile were carburetor equipped cars. I don’t think this treatment is necessary with today’s modern fuel-injected engines.

The only, very limited, truth to that notion is that some recent cars with electronically controlled transmissions ‘learn’ the driving habits of the driver and modifies shift points accordingly. But this is not what you’re asking about. The Prius will be fine for what you want to do.

I respectfully disagree. At 6000 rpm the forces on the piston are higher than at 1000 rpm, All metal deflects when force is applied to it, it’s just a matter of how much. We could be talking .001’s of inches here, but it doesn’t take much to cause damage.

I agree.
Dag’s post really made me chuckle.

It also made me wonder if he is related to pleasedodgevan!
This type reponse from PDV would not have surprised me, as his sense of humor is well-known on this site. Prior to this, I don’t recall seeing Dag’s sense of humor come to the surface.

More please, Dag!

Yes, some do this. However, they will relearn the new driver in a week or two anyway.

Which part is streching?the crank throw or the distance between centers on the big and small end of the rod, are the piston ring lands changing position on the piston?is the piston pin hole moving around?

We make mistakes when we apply the conditions and pecularites of a 30’s,40,s 50,s IC engine to todays engines. We also make errors when we want to compare what happens on the track to a car overall (not just the engine).

I agree, Oldschool. A ‘city’ car’s engine will experience the same range of RPMs as a ‘highway’ car, if not greater, so the wear patterns would be no different.

Our Prius can go on cities and highways fine.

7075-T6 wrote-I respectfully disagree. At 6000 rpm the forces on the piston are higher than at 1000 rpm, All metal deflects when force is applied to it, it’s just a matter of how much. We could be talking .001’s of inches here, but it doesn’t take much to cause damage.

That’s correct although the stretch can be much more depending on the rod type/material. The laws of physics did not change over the decades. There are also several interfaces that are subjected to the stress. If anyone is doubtful and does not have the proper materials to review, just google on rod stretch for some information.

Oldschool, keep in mind all materials, including metal, are elastic to some degree.

oldschool wrote- The stroke of a engine is not dependant upon engine RPM. The pistons travel the exact same path no matter what the engine RPM.

Are you absolutely sure you want to stand behind that statement??

There is nothing absolute but we are talking a difference that would create a interference point in regards to the ridge left in the cylinder, I just dont see it streching that much. I don’t doubt that materials strect under stress,heat and cold, just look at how many parts that you either heat or freeze to make installation easier. But this difference is not enough to create a engine damaging condition from the rings being forced into a new contact area.

Think pratical.

Interesting. An argument about the modulous of elasticity of the various materials that hold the mass that is the piston in place at a particular rate of change in velocity. The questions that inertia raises. Yeah, stuff stretches. And crankshafts bend. For those with enquiring minds, there are websites engineers visit for answers to these questions. Actually, today’s software does the labor for us.

In practical application, these things are only important to the designers. Since all engines in daily drivers constantly go through their ranges as we accelerate, stop, and pass the elderly, these details matter not.

The car will be fine. Enjoy your prius.