Before buying a car one of the major concerns is...Whether to buy a petrol car or a diesel Car. This question baffles many before they can actually take a decision to but a car. So how shall we go about solving such a problem? Is there any quantitative method or just experts opinion can be taken. In a one of its kind way I have tried to analyze the problem quantitatively by having some assumptions. The figures can change but the procedure remains same. So the procedure is as follows:

Let us assume that you Drive the car for say 200000 kms.

(Highly Highly Optimistic for Indian Roads).

Let the price of Diesel Car Rs.600000.

Let the price of Diesel Car Rs.500000

So the car cost for Diesel = 600000/200000 = Rs.3.00/km

And the cost for Petrol Car = Rs.2.50/km

Next we assume petrol at Rs. 50 and Diesel at Rs.36/litre.

Also let mileage for Petrol Version be 10 kmpl and that of Diesel be 12kmpl

Diesel cars generally give more mileage owing to better fuel efficiency of Diesel as a fuel

Running Cost for Diesel = Rs.3 / litre

Running Cost for Petrol = Rs.5 / litre

Also if we consider the maintenance cost. Suppose cars go for servicing once in 120 days.

Say a petrol car on an average needs around Re.4000 for maintenance.

Whereas a diesel car needs Rs.7000 for maintenance.

Generally Diesel cars needs more frequent and more costlier maintenance.

Solving the equations we get:

We get if daily run of a car is more than 17 kms/day then Diesel cars will be cheaper.

On the other hand if daily run is less than 17 then petrol car will be cheaper.

If it is near to 17 the better opt for Petrol Cars as they will produce less noise, less vibration and will keep our planet clean.

Last but not the least a petrol car runs on high engine speed whereas a diesel car runs on high torque. So wear and tear of different part will be different in the two breeds.

Note:- Individual figures are assumed and may change with respect to the situation.