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Running a car 24 hours a day

On a recent Car Talk show (podcast) a caller wanted some advice for a driving their car from Buffalo to San Diego. "Is it better to drive for a couple hours, then then stop to rest the car, or is it better to just keep on driving? " VW gasoline powered sedan of some type. Tom thought the car should be given a rest once in a while. Ray focused more on the driver, saying the driver is better off to stop take a rest. But there were multiple drivers in this case, so theoretically they could drive in shifts and drive 24 hours a day if they wanted.

Wouldn’t driving 24 hours a day non-stop and never stopping except for gasoline and haircuts actually be the best for the car’s mechanicals? Or would the car somehow benefit mechanically by taking a break every few hours?

I don’t know, but I’ve done this - 50 years ago. I suspect that fewer starts contributes to greater total mileage, as long as you keep up the maintenance. On 1 of my trips the block cracked while I was driving. I asked the owner if something wasn’t wrong when the thermostat started reading high, but he blew me off. I was hitch-hiking once when a wheel left the car on I-40 in Oklahoma: that was exciting. I opened the door, considered jumping for a nanosecond.

I feel the driver rest is more important than the car. Approaching 200k miles in a variety of car trips, I think it matters not to the car. Sure one could say there are x amount of times a starter motor will work, but I call that a non factor.

I did this once, too. We had to get from San Francisco to Cape Cod for a wedding, and 9-11 shut down all air transport, so 4 of us rented a mini-van and drove it pretty much non-stop except for the usual fuel and bathroom breaks. We brought food with us in a cooler and in boxes and made sandwiches, etc., along the way. There were lots of people doing similar drives, ad hoc groups who met in a hotel somewhere and got together to rent a car. It was a very strange time in America. The minivan ran just fine, we averaged 71 or 72 mph according to the onboard computer, and made it from coast to coast in about 52 hours, including all the short stops. Running a car 24 hours a day, day after day, only requires a bit of attention to fluids and fuel. Police departments do it a lot.

It is better to run the car for 24 hours without stopping. Why? Heat-cool cycles add more stress to the car than getting to operating temp and keeping it at operating temp. If all systems are operating properly, the car should not over-temp any system forcing a stop.

Really, it is a very silly question for 2018. Not for 1961 maybe, but it is for 2018.

Then there are practical matters like food, rest stops, and driver swaps…


That is what I thought when I saw the post heading.

saw a 2015 chevy duramax pickup for $25k but owner said it had 315k miles. which is nothing compared to a hyundai. i figure he stopped a few times in 3yrs

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Although it may be silly to ask, I think the reason it was asked was because one of them (I think Tom, but cannot remember for sure) indicated that stopping the car was better to allow it to rest. I couldn’t tell if he was serious or joking and couldn’t believe the answer if he was serious. I had no idea why they would say the car needs rest. Now if you’re operating the car in a stressful environment, it makes sense. Say, towing uphill, so you may want to allow transmission fluid to cool or going down a long grade and you stop to allow brakes to cool.

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Agree! Cars don’t need bathroom breaks and steady normal speeds are best for the engine. My late brother and his wife used to drive across the country non-stop by taking turns driving. He had a big rear drive Cadillac and the back seat was good for sleeping.

They would do about 2500 miles on one stretch, but always checked the oil when gassing up.

Years ago with the first Cannonball Sea to Shining Sea Memorial Trophy Dash (the full name) some participants drove a full size Cadillac West for a New York owner. He was not told how the car would be driven! They probably rested for a few days before getting the car back to its owner.

The car suffered no ill effects even when drive at 100 mph for hours .