Diesel fuelled vehicles have been under intense scrutiny in the UK for many years and have been demonised to some extent in part to the rapidly changing attitudes towards global warming and the effect of co2 and NOx on the environment.
Certain legislations such as London's ULEZ are also in place which effectively punishes a driver of a diesel vehicle with extra charges. Despite diesel being more economical on a miles per gallon basis it would seem the tide has turned on this fossil fuel as the harmful emissions are simply too much if a nation wishes to be carbon neutral or better.
The rise of incentives for electric/hybrid vehicles and petrol engines closing the gap in terms of miles per gallon makes it even tougher for someone who wants a diesel to get an uncomplicated deal. Yet, diesel vehicles are still available to lease and provide better than ever performance and it has to be said they are less harmful than what they used to be.
In 2018, the vehicle excise duty (sometimes referred to as road tax) increased for diesel cars. Before this change, they were on the same band as petrol cars. VED is included in a lease and it isn't a cost you will have to pay for yourself but it does mean that the overall cost of the vehicle itself goes up.
An example, if the VED of your diesel vehicle is £300 more than what it used to be then you would expect the lease price to go up by £23 a month. This is based on a calculation of £300 a year extra, multiplied by 3 years and then divided by the term of a 3+35.
Alongside this charge are the ULEZ charges, some parking surcharges and some road-specific fines in London which may or may not extend to other cities such as Birmingham and Manchester in the future.
New diesel cars built after 2017 need to be Euro 6 compliant which regulates the maximum about of emissions a car can produce before they can be sold. The problem this caused for diesel cars isn't just the co2s but rather the more harmful NOx (nitrogen oxides) which diesel cars pump out much more than any other type of fuel.
However, this was more of a problem of older diesel cars without modern technology to make them cleaner. All diesel cars available to buy new today are Euro 6 compliant, however, more trouble could be on the horizon when Euro 7 comes in to play.
DPFs have existed in diesel cars for decades, however, you may never have considered why they're necessary and that they need regular attention and maintenance.
A DPF is needed to reduce the already harmful fumes a diesel engine generates by trapping soot. Without a DPF the presence of black smoke coming out of cars would be far more common. Often, if you see a car emit black smoke it is because of a full or faulty DPF.
These filters can't go on forever and will eventually become clogged up but this would only happen to vehicles not being serviced properly and subject to short journeys and low speeds. The average life of a well maintained DPF is 100,000 miles.
A diesel car which regularly drives a decent distance will help regenerate the effectiveness of a DPF and extend its life. However, if the DPF filter is not able to regenerate the vehicle will emit significantly more harmful emissions and the filter itself could become damaged and need replacing at cost.
Modern vehicles will have a warning light when the filter needs a forced regeneration, if this light is ignored then the warranty will not cover the cost which could be as high as £1,500!
This is something a prospective diesel buyer or leaser should consider - if you only need a vehicle for short journeys in urban environments then a diesel car can incur greater costs just to keep the DPF going. This is especially true for people who drive an older diesel car.
Most modern diesel cars made after 2015 will now have a diesel exhaust fluid system (DEF) sometimes known as AdBlue which helps break down the NOx in the exhaust system. AdBlue is a liquid mix of urea and de-ionized water which breaks the chemicals down harmlessly before they leave the car.
Your AdBlue levels need to be topped up much like your oil or engine coolant - they should be topped up during a normal service. This can add to the cost of the service but covered if you have a maintenance package as it classes as a consumable.
This cost could build up with high mileage contracts. There is also the danger that if the AdBlue warning light is ignored that the car won't start until it's topped up as it will no longer be Euro 6 compliant and producing more pollution than is permitted.