This figure does not include  the SIAM's tally in the mid-size category that includes Honda Siel, General Motors and Fiat India, which do not field diesel variants in the A3 segment.

Diesel mid-size cars on an average are priced 15.5 per cent more than the petrol variant. Overall, the mid-size category, petrol and diesel models included, grew by 14.6 per cent.

Diesel passenger vehicles command about 35 per cent of the entire category in the country and have been growing between 6 and 9 per cent over the last two years.

Industry forecasts point to diesel vehicles cornering about 50 per cent of the entire passenger vehicles segment in India by 2010. In Europe, about 46 per cent of vehicles plying currently are diesel and this number is expected to reach 65 per cent over four years.

For legacy auto majors like Hindustan Motors [Get Quote] - HM,  diesel variants of Mitsubishi Lancers sold in the last financial year was as high as 94 per cent of the total sales. Interestingly, sales of  HM's iconic Ambassador  petrol cars were higher than its diesel versions. The petrol-diesel mix was in the ratio of 40:60.

"With much of the Ambassador car sales coming from government departments, fuel economy is not a primary concern," said the company source, who requested anonymity. Ambassador petrol versions also run on CNG and are widely used as taxis.

Though sales figures for  Maruti [Get Quote] Suzuk's Dzire diesel variant are not available, the company says customers' preference towards its diesel  vehicles is clearly evident in the sales figures of the diesel Swift (compact category), which sold over 55 per cent till date.

According to the SIAM data,  Hyundai sold about 33,000 units in the mid-size car category, out of which between 70 and 80 per cent sold were diesel variants. Hyundai sells the Accent (only petrol) and the Verna (both petrol and diesel versions).

Ford, which sells its diesel variants mainly in the Fusion & Fiesta models logged over 29,000 units in domestic sales, out of which over 70 per cent were in cars equipped with the diesel Duroatorq engines versus those strapped with the Duratec petrol engine variant.

Aided by its mono-brand Logan, Mahindra Renault sold over 25,000 cars, out of which 68 per cent were in the diesel segment and the rest in petrol. The Logan has a market share of 12 per cent in this mid-size car segment.

Industry sources say the reasons for diesel engines outselling petrol cars are manifold. Diesel is about 30- 40 per cent more fuel efficient over petrol.

"All the new diesel engines  comply with Bharat Stage-III emission norms , and are frugal, fast, relatively refined and ultimately have the ability to provide a satisfactory driving experience," said Nalin Mehta, COO, Mahindra Renault. The latest development in diesel engines has also made today's diesel cars equal to a petrol variant.