Types of fuel for cars – Which is the best?

Petrol or Diesel?

You’ve made the big decision to buy a new car, but should you opt for a petrol or diesel engine? This choice can play a vital role in your final decision, so if you’re struggling to make up your mind, it can be useful to look at the pros and cons of both options.

Considering the costs

It is widely accepted that diesel cars are more expensive to buy, with manufacturers sometimes asking for around £1000-£2000 more for diesel models than their petrol equivalents. If you’re doing a lot of miles, then the higher fuel efficiency of diesel cars can give you better value for moneyif you drive many miles per year

Although diesel cars may be more fuel efficient in the long run, you may want to keep in mind the high cost of maintenance and servicing. Diesel cars are more expensive to buy due to their advanced fuel technology, but in turn this means it costs more to service them. It’s also worth considering that insurance prices vary for diesel and petrol cars, so it can be useful to get a few insurance quotes to ensure you’re seeing the full picture.

It’s important to consider the resale value too. According to the Money Advice Service the resale price for diesel cars does tend to be more than their petrol counterparts, so this could mean your vehicle’s value holds better if you decide to sell.

The type of car you decide to purchase can have a big influence on all of the factors detailed above as well.

Fuel price and consumption

Although in previous years diesel has been cheaper than petrol, an increase in demand means that it’s now more expensive per litre. However if we look at fuel consumption, diesel engines use 15%-20% less fuel than their petrol equivalents, meaning less visits to the fuel pump.

We can’t predict fuel prices in the future, but we do expect diesel cars to continue to be more fuel efficient.

Behaviour on the road

Driving the two types of car can be quite different, and this is where personal preference plays a larger role. Diesel engines are notorious for being noisier than the more refined petrol engines, but this problem has improved over the past few years. It’s also worth noting that diesel engines have increased torque, giving it more pulling power at lower revs – if you’re looking at purchasing a van, or if you need a trailer this could be desirable – it just depends on what vehicle you have decided on.

Diesel cars are most suited to those who drive many miles per year, or frequent motorway drivers. In this case, diesel cars can serve you well, as their engines are highly efficient at high speeds. For someone who drives shorter distances such as city driving, the school run or just a few miles to and from work – then a smaller petrol car can prove easier to maintain both practically and economically.

Most modern diesel engines are equipped with a diesel particulate filter, which can clog if the vehicle is not driven at high speeds, such as on a motorway, often. These filters are costly to replace, so it if you tend to steer clear of motorways, this is something to think about.


In the past diesel cars have offered significant savings on tax, which meant that the initial cost difference of the car compared to the petrol engine was recouped within a few years. Recent changes in car tax legislation mean that only the tax payment for the first year is based on CO2 emissions if you buy a new car after April 2017 and the second year of ownership onwards comes at a standard car tax rate of £140 per year for petrol and diesel cars and £130 for alternative cars such as hybrids (this may be higher if a list price of >£40,000 is purchased).

This change means it will take longer to recoup the extra money spent on the more expensive diesel engine. Potential savings between petrol and diesel cars will therefore be based largely upon fuel consumption and your annual mileage moving forwards.

If you’re buying a car or van that was registered before 1st April 2017, previous tax rates still apply, which will increase the chances that a diesel vehicle will provide better value for money, however, it is worth checking this before you purchase a vehicle. Information on the new tax legislation for cars can be found at the following GOV.uk page.

Hybrid cars

Many manufacturers are now offer “hybrid” cars – this means that in addition to having a petrol or diesel engine, they also use an electric motor. This can increase the fuel economy of a car which may reduce running costs as well as being better for the environment than traditional petrol or diesel cars. Hybrid cars may also avoid congestion charges.

Not all hybrid cars work in the same way; some cars can run solely using the electric motor at low speeds, whilst others only use the electric motor to provide the main engine with extra help. Plug-in hybrids are cars that have larger batteries and can run for longer on the electric motor alone. But you need to recharge these at electrical outlets after a certain level of use. These cars fall somewhere between standard hybrids and full electric cars.

Weighing up the options

The answer to the petrol versus diesel question is not black and white, but it is clear that you need to weigh up a number of factors. To help you make your choice, here’s a reminder and checklist of things to consider when thinking about the engine type that’s best for you:

  • The price of Diesel vs. Petrol cars – both buying and maintaining
  • What will your fuel consumption be like?
  • Diesel vs. Petrol Fuel prices
  • Your usual annual mileage and the type of driving you do
  • Environmental concerns

Have you found the car of your dreams, but need help to buy it? At Moneybarn we provide car finance for bad credit. Why don’t you get in touch? We are happy to help!

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