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DIESEL v/s PETROL. What are the pros and cons?  


Diesels are generally dearer to buy but in the past have held their value better. Though this may change.

Over 2007/08 diesel fuel in the UK became about 10% more expensive to buy than petrol, but regained parity on 2009.

Diesel automatics can lose a lot of the economy advantage due to torque converter losses.

Diesels may reduce fuel bills, but diesels built since Year 2000 can double and even quadruple the bills for everything else.

The problems tend to start after about 3 - 4 years old but can start earlier:

Dual mass flywheel failures on manuals leading to failures of drive, often incorrectly prescribed as clutch failure when in fact it is the dual mass flywheel that has failed: £800 - £1,500.

Turbo and intercooler failures: £1,000 - 1,500. The problem is often caused by carbon blockng the oil feed pipe to the turbo bearing due to the driver switching off the engine when the turbo is red hot. Esplained elsewhere.

EGR failures: £300 - £600 

Manifold swirl flap failures: £300 +

Injection pump failures £1,000 - £2,000

Injector failures £250 - £1,500

Diesel particulate filter failures £500 - £1,500. It was always illegal to remove a DPF, and from February 2014 has been tested for as part of the MoT. 

Glowplug failures up to £1,000 if they come out. Up to £3,000 if they snap and the head has to be removed to extract them.

Depending on the crude oil itself there is a limit to how much low sulphur diesel can be refined from each barrel of crude, unless new types of multi million pound refineries are built.

Unfortunately, worldwide demand is relatively greater for the amount of diesel that can be refined from crude than it is for petrol.

It's used for trucking, shipping, railways, heating, farming, etc.

So really, everyone who uses it in private cars is putting up the cost of diesel for more essential uses, which puts up the price of everything.

Europe has more diesel then the UK because it can store more, which is why diesel is dearer in the UK than in Europe.

UK fuel tax on petrol and diesel is the same at 50.35p per litre + VAT, + VAT on the fuel itself.

Fuel Duty on Petrol and Diesel = 50.35p/litre

Fuel Duty on Biodiesel = 30.35p + 2p = £32.35p

Fuel Duty on Bioethanol = 30.35p + 2p = £32.35p

Fuel Duty on LPG = 16.49p/kg + 4.28p/kg = 20.77p/kg

Fuel Duty on CNG = 13.7p/kg + 2.89p/kg = 16.59p/kg

Fuel Duty on Red Diesel = 9.69p + 0.38p = 10.07p

Fuel Duty on Fuel Oil for heating = 9.29p + 0.37p = 9.66p 


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