Diesel cars are being offered with up to £5,700 off the price of a new car.
Certain cars have had over 25 per cent discount slashed off the overall cost.
Concerns over the detrimental effect of the emissions the fuel type emits and general uncertainty over the future of the diesel has caused prices to tumble.
A new investigation between June and August found “achievable discounts” of almost £3,000 off list prices.
Analysis by mystery shoppers across 7,500 new cars on sale found that drivers are set to make considerable savings off new diesels.
Drivers could make possible savings of up to £5,700, which is equivalent to 22 per cent off a Mitsubishi Outlander.
Steve Huntingford, Editor of What Car?, said: “Although overall discounts have remained static over the last quarter, savvy buyers have still been able to score a bargain using our Target Price data, especially during August, which we had predicted would be a bumper month for deals.
“It’s interesting to see dealers finally start to offer bigger discounts on large SUVs because traditionally these have been some of the hardest cars to negotiate on.
“However, large SUVs tend to be diesels and the negative publicity and threat of future diesel taxes could well have played a part.
“The fact that there are so many models for people to choose from now has probably also played a part.
“We will wait to see if this trend continues with the introduction of the 68-plate registrations in September.
“Buyers should continue to check our regularly updated Target Price guide to see when is best to sign on the dotted line.”
What Car? found that average discounts available across the new car market as a whole were 8 per cent between June and August.
This is worth around £2,500 off list prices, despite deals on small cars, family cars and executive cars declining.
Should you buy one?
Diesel cars are still useful for motorists covering long distances as usually, they are more economical in terms of fuel.
In cities or for motorists that cover shorter distances then they perhaps aren’t as suitable as the filters that are fitted to reduce emissions aren’t as effective when cold.
They typically take around 20-30 minutes driving at motorway speeds to warm up and be effective.
SUVs tend to produce higher CO2 emissions compared to a city or small car which means that you may fork out more for tax in an SUV, especially with the new diesel tax rates applied.
Diesel cars will be phased out by 2040, along with petrol, in plans to clampdown on emissions.
In addition to this, a number of car manufacturers have stopped selling new diesel-engined vehicles such as Volvo and Porsche, with others planning on phasing them out such as FCA (which owns Fiat, Jeep, Alfa Romeo among others).
Top 10/Bottom 10 manufacturer Average cash discounts – Q2 (June to August):
1. Seat – 11.93 per cent
2. Renault – 11.74 per cent
3. Volkswagen – 11.52 per cent
4. Citroën – 11.40 per cent
5. Smart – 11.13 per cent
6. DS – 10.36 per cent
7. Vauxhall – 10.20 per cent
8. Peugeot – 9.84 per cent
9. Ford – 9.79 per cent
10. Mercedes-Benz – 8.70 per cent
1. Porsche – 0.00 per cent
2. Dacia – 0.98 per cent
3. Ssangyong – 2.08 per cent
4. MG – 2.79 per cent
5. Infiniti – 3.01 per cent
6. Mazda – 3.95 per cent
7. Subaru – 4.17 per cent
8. Land Rover – 4.33 per cent
9. Jeep – 4.54 per cent
10. Lexus – 5.22 per cent
Top 10 model discounts (August 2018)
1. Fiat Tipo 1.4 Easy
OTR Price: £14,320
Discounted Price: £10,515
Discount: 26.57 per cent
2. Volkswagen Passat 1.4 TSI S
OTR Price: £22,195
Discounted Price: £17,019
Discount: 23.32 per cent
3. Vauxhall Astra 1.0T Ecotec SRi
OTR Price: £21,210
Discounted Price: £16,385
Discount: 22.75 per cent
4. Mercedes-Benz SL SL 400 AMG Line 9G-Tronic
OTR Price: £77,395
Discounted Price: £60,314
Discount: 22.07 per cent
5. Seat Toledo 1.0 TSI 110 SE
OTR Price: £17,330
Discounted Price: £13,516
Discount: 22.01 per cent
6. Mitsubishi Outlander 2.2 DI-D 2
OTR Price: £25,920
Discounted Price: £20,223
Discount: 21.98 per cent
7. Peugeot 508 2.0 BlueHDi 180 GT auto
OTR Price: £35,170
Discounted Price: £27,635
Discount: 21.42 per cent
8. Vauxhall Mokka X 1.4T Ecotec Active
OTR Price: £22,035
Discounted Price: £17,396
Discount: 21.05 per cent
9. Citroën C4 Spacetourer 2.0 Blue HDi 160 Flair EAT8
OTR Price: £30,285
Discounted Price: £24,562
Discount: 18.90 per cent
10. Volkswagen Golf SV 1.5 TSI 150 GT Evo DSG
OTR Price: £27,870
Discounted Price: £22,731
Discount: 18.44 per cent
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