Petrol, diesel or CNG: which fuel actually suits you?
The fuel badge is the single decision that changes your running cost the most, and it's the one buyers get talked into for the wrong reasons. Here's how to pick in five minutes, using your own numbers.
Why the showroom pushes the one it does
A salesperson's fuel recommendation often tracks what's in stock or what carries the fatter margin, not what suits your week. Diesel gets pushed to people who'll never do the mileage to justify it; CNG gets waved away by dealers who'd rather sell the pricier petrol automatic. You need your own rule, not theirs.
That rule is simple: the fuel decision is a payback calculation, and the only input that really matters is how many kilometres you drive a month.
The three numbers that decide it
First, your real monthly mileage — not your best guess, but the honest average across a year including the odd road trip. Second, the price premium of the fuel you're considering over plain petrol (diesel is typically around a lakh more; factory CNG around ₹90,000 more). Third, the saving per kilometre that fuel gives you.
Divide the premium by the monthly saving and you get the months to break even. Below that, you're subsidising the badge; above it, you're saving. We do this calculation with buyers every week, and it quietly settles most arguments.
What each fuel costs you beyond the pump
CNG trims the boot — the cylinder lives back there — and softens performance, because the same engine makes less power on gas. Diesels cost more to service and, in some cities, face stricter age limits on registration. Petrols give up nothing except a slightly higher fuel bill. None of these is a dealbreaker, but all of them belong in the decision.
Resale matters too: a well-kept CNG or diesel can be harder or easier to sell on depending on your city's buyers. It's worth a thought if you change cars often.
What we'd do
For the typical city buyer doing under 1,200 km a month, we'd take the petrol every time and not look back. For a high-mileage commuter who lives in traffic, we'd take the factory CNG and enjoy the fuel bill. For someone genuinely eating highway miles — a sales job, a weekly intercity run — we'd take the diesel and let its torque do the work.
Tell us your real monthly running and the two cars you're weighing, and we'll run the exact break-even for you. It takes five minutes and it's the cheapest advice you'll get all year.
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