That does not necessarily mean trading in your GMC Yukon Dena XL for a Toyota Yaris. Odds are, the person who's been driving the big, ritzy Yukon either needs something fairly large and fairly functional or craves the tall seating position and safety-in-size benefits of a larger vehicle. That means the logical downsize here is not to a Yaris or some other pint-sized runabout, but, say, a Toyota Venza car-based crossover.

Obviously, the Denali is bigger and more powerful, and its tow rating is twice that of the Venza. But the Venza is still a good-sized wagon with a 268-horsepower V-6 and all-wheel-drive. Consider the Venza an interim ride, the sort of vehicle that weans the owner off a gas-guzzler.

And if you move from the Denali to the Venza, and if you typically drive 20,000 km a year (split 55 per cent city driving/45 per cent highway), the annual fuel cost savings are huge: $1,188. If you hold on to a new vehicle for eight years, it all adds up to fuel savings worth $9,504 - until trade-in time arrives.

Oh, and did we mention that a loaded Venza ($32,250) costs $43,910 less than the Denali at $76,160? We tracked down fuel-savings figures using fuel consumption ratings and the online cost calculator provided by Natural Resources Canada at oee.nrcan.gc.ca, look under Transportation and the Tools section. According to the numbers there, the Venza is rated at 11.5 L/100 km city and 7.9 highway. That translates to 1,980 litres of fuel used per year.

The Denali? It is projected to slurp down 2,880 litres of premium fuel for an annual cost of $3,168. Yes, size matters, alright.

The massive Denali weighs in at 2,648 kg, while the Venza tips the scales at 1,835 kg. Oh, and under the Denali's hood is a 6.2-litre V-8 rated at 17.5 city/10.6 highway. That powerplant uses pricier premium fuel.

So the downsizing strategy seems obvious.