6 Ways to Break in a New Car Engine

BMW Car in sunset

Should you ‘break in’ a new car? It’s a question with a lot of answers, but most experts and manufacturers agree it’s a good idea. While modern engines are tougher than previous generations, driving gently for the first 1,000 miles or so is still recommended if you want to guarantee the long-term health and performance of your engine.

Here, we take a closer look at how to break in a new car engine, covering the techniques you can use to give your new car time to adjust to everyday driving conditions.

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Do You Need to Break in a New Car?

When you’ve picked up the keys to your new car, you might be tempted to find out just what it’s capable of. But pushing a new engine too hard in the first 1,000 miles could have repercussions in the long-term, so it’s important to break in the car before taking it anywhere near the red line.

What do we mean by ‘break in’? It comes down to giving the engine time to adjust and operate evenly after rolling off the production line, so no parts are put under excess strain early on. Most manufacturers recommend breaking in new cars, and you can find this information in your vehicle’s manual.

Breaking in an engine ensures that early engine wear is kept to a minimum, and that the oil flows smoothly and evenly through all moving parts. It also gives the piston rings (the connector between the cylinder and the piston) time to seat properly, and allows the engine and transmission time to adjust to each other.

Oil Car Engine

How Long Does It Take to Break in an Engine?

The time it takes to break in an engine differs by manufacturer. Most recommend avoiding high RPMs in the first 1,000 to 1,500 miles; a maximum of 3,500 RPM is the ballpark for diesel engines, rising to 4,500 RPM for petrol.

What Are the Benefits of Breaking in an Engine?

There are a handful of reasons why it’s a good idea to break in your new car, including:

  • Better fuel economy – New engines don’t reach peak efficiency until you’ve done a couple of thousand miles, so driving within the manufacturer’s break in guidelines will help maintain good fuel economy. You should also add the relevant Redex fuel additive to ensure peak engine performance and efficiency.
  • Better performance – Breaking in a new car will help to improve engine performance in the long-term. That’s because friction is limited and parts are balanced and working together efficiently, ensuring better power delivery.
  • Improved long-term engine health – With parts working at their best and oil flowing smoothly through the system, breaking in your car for the first 1,000 or so miles ensures optimum engine health in the years to come.

6 Techniques for Breaking in a New Car

If you’re keen to take great care of your car from the very first mile, take a look at our tips on how to break it in to ensure optimum engine health. We’ve also included advice on driving safely within the first 1,000 miles to let the tyres, brakes and suspension bed in.

1.      Don’t Push the Engine Too Hard

In the first 1,000 miles, don’t push the engine to the red line. This can put a lot of strain on the piston rings and cylinders, and can worsen manufacturing imperfections.

As a rule of thumb, anything up to 4,000 RPM is safe in the first 1,000 miles. After that, you can gradually increase the RPM without any negative effects.

Car Gearstick

2.      Change Gear at a Low RPM

The break in process allows time for the engine and transmission to adjust to one another, so changing gear at a low RPM will avoid unnecessary wear and tear. This can also help with fuel economy, so changing gear at low revs is a good habit to get into.

A lot of new cars feature a ‘change up/change down’ function, which prompts you on when to change gear to maximise MPG. It’s worth sticking to this within the first 1,000 miles as a good indicator of a safe RPM in which to change gear.

3.      Don’t Floor the Accelerator

Tempting as it may be to floor the accelerator when you get your new car out on the open road, this can put a lot of strain on the engine oil, piston rings and cylinders. What’s more,  aggressive acceleration when the car is cold can be harmful no matter how many miles you’ve covered.

In the first 1,000 miles, accelerate gently and work through the gears quickly, before the RPM can build too high. This will ensure smooth engine performance while helping the transmission bed in.

4.      Avoid Short Trips Which Don’t Give the Engine Time to Warm Up

Whether heading to the local shops or dropping the kids at school, short trips like these aren’t ideal for brand new cars. Cold engines have to work harder, putting a lot of strain on the oil delivery cycle, so you should only drive your new car if you’re planning a longer journey that lets the engine warm through.

In the same breath, you should also run the car at a gentle pace after it’s been working hard on a long drive. For example, if you’ve driven on the motorway for a good distance, you should drive gently through town before you reach your destination, as this will allow the engine to cool rather than coming to a hard stop.

5.      Don’t Tow Heavy Loads

While you might be dying to hitch up your caravan and hit the road in your new car, towing heavy loads isn’t great for new engines. Towing puts added strain on engines in normal driving conditions, but can be particularly damaging for new cars that haven’t been broken in.

Hold off planning any caravan holidays or days out with your horse for the time being; we’d only recommend towing heavy loads after 1,000 miles of driving to give the engine time to adjust.

6.      Adjust Your Driving Style for Safety

It isn’t just the engine you need to think about when breaking in a new car – the tyres, brakes and suspension need time to bed in too. Cars don’t handle as well when they’re straight off the factory floor, so a cautious approach is needed to maximise safety.

For the first 200 miles or so, tyres don’t offer the level of grip which you can expect after that. That’s because they’re covered with a lubricant which is applied during the manufacturing process, and which takes a couple of hundred miles to fully wear off.

Brakes also need time to adjust, as the pads and disc start to work together and develop friction spots, which ensures smooth, effortless stopping performance. Similarly, shock absorbers and springs won’t fully bed in for at least 1,000 miles, affecting handling and performance.

At Redex, our fuel system cleaners and high-performance engine oils can help your car perform perfectly from the very first mile. For more information, and to browse our complete product range, visit the Redex homepage today.