An Engineer Explains Five Things You Should Never Do With A New Car

An Engineer Explains Five Things You Should Never Do With A New Car

New cars need to be broken in. If you’re not careful during the break-in period you can reduce the performance and longevity of your car’s engine, or even damage it. Here are five things you should avoid if you just bought a brand new car.

In this video from the Engineering Explained YouTube channel, mechanical engineer Jason Fenske explains the activities that cause the most strain on your vehicle during the break-in period. Here’s what you should avoid:

  1. Don’t floor it: Your shiny new car may be fast, but hitting the accelerator and pushing the engine at full throttle isn’t a good idea unless there’s an emergency.
  2. Don’t shift at redline: Shifting up in gear is usually optimal at or near redline, or maximum RPM. Shift at lower RPMs during the break-in period.
  3. Don’t use cruise control: You want to vary your engine’s RPM while driving during the break-in period. Cruise control is going to set the engine at one RPM.
  4. Don’t travel super short distances: During the break-in period you want to get your vehicle’s engine up to operating temperature each time you drive it. Short trips don’t always allow that.
  5. Don’t tow anything: Towing puts a higher load on your engine. To tow something, your car has to move more weight, and it needs more throttle to do so. See number one.

The length of the break-in period varies for every vehicle. Some can be as short as a few hundred kilometres, some can be as long as several thousand, and some cars may even ship already broken in. Check your vehicle’s manual to find out.

5 Things You Should Never Do In A Brand New Car [YouTube]


  • This bloke may be an engineer but I doubt he’s a mechanic.
    Items 1 and 2 were true years ago but few manufacturers tell their owner this these days. The strongest cars for type I have driven were always those that were belted from day one. Old truism: Run ’em in quick and they go quick.
    Why not us cruise control? Engine speed is determined by road speed and gears, not cruise control.
    Common sense should tell most people not to hang an eight metre caravan off a new car, but your average box trailer is likely to do more good than harm. Throttle opening should be varied along with engine speed. Short spurts of open throttle at medium to high revs can be beneficial.

  • Are you a mechanic?

    I have an old truism too. Don’t follow the advice of the uneducated masses on the interwebs!

    The manual for my and my wife’s car, both less than 2 years old, say to pretty much follow this engineer’s advice.

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