On page 17 of the January/February issue of Truck Trend, a chart of full-size-truck mileage ratings touts the fact that the Big Three now have models that can achieve 20 mpg-plus highway mpg.
We're seeing trucks coming out of the factories now with gear ratios barely over 3.00:1. In EPA testing, this is surely how they achieve the 20-plus-mpg figures. Sure, in a theoretically perfect world, driving on a flat Interstate highway with the cruise set at 65 mph, you will see good mpg because the tall gearing will keep the rpm down, and since the road is flat there is little load on the engine. However, the problem is this isn't a theoretically perfect world we live in. The U.S. has curves, hills, mountains, stoplights, heavy traffic, all kinds of obstacles we drive in every day. When driving a 5000-plus-pound pickup truck, the last thing you want is a tall gear ratio under these circumstances. Note how the city EPA numbers are all around 14 mpg for each brand? Those numbers haven't improved at all on any model (except the GM hybrid). The reason is because the tall gearing is making the engine work harder in normal driving conditions, which counteracts the other beneficial things they've done such as weight reduction.
The Big Three are making changes to their trucks that will allow them to post excellent highway mpg numbers, and get people to buy full-size trucks again. The truth is, the average person is going to see mileage numbers with these trucks closer to the city figures, which haven't changed from trucks of five years ago. The Big Three have gone about improving the EPA numbers in the wrong way.
Shawn Crowe
Lawrenceburg, Kentucky
Your point is valid and we are aware pickup EPA numbers remain optimistic, noting in tests how close we get to those ratings and under what conditions. The taller axle ratios have been mildly countered by the switch to six-speed automatics, so you can still pull a grade but will downshift a few times to do it. Many pickups were previously used as cars, but those days softened somewhat with 2008 fuel prices and the economic malaise. G.R. Whale may have been onto something in his November/December column where he suggested pickups should be tested at GVWR, or while towing.
- Truck Trend
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