A recent Consumer Reports survey claims the spring run-up in gas prices has had a real impact on American drivers. Fuel economy beat quality and safety as the most important factor in a new vehicle buying decision with two-thirds of respondents saying they expect their next vehicle to get better fuel mileage than the one they’re driving now. In addition, more than a third of the participants said they are driving less than they did a year ago.

While 90 percent of those surveyed said money was the primary motivation for wanting a more fuel-efficient vehicle, 62 percent also said they wanted to be more environmentally friendly and 56 percent were concerned about America’s dependence on foreign oil.

The survey showed car owners willing to consider different ways to trim their gasoline expenses, from simply downsizing vehicle or engine size to alternatives like hybrids, electric cars, or diesels. Almost three-quarters of those polled would consider an alternatively fueled vehicle, with flex-fuel and hybrid models leading the way. Younger buyers were more likely to consider an alternatively fueled or purely electric vehicle than drivers over the age of 55.

When asked about a replacement for their current vehicle, small cars were named by the highest percentage of respondents. The next-largest percentages went to larger sedans and midsized SUVs. CR noted that their survey showed owners would be less likely to replace their current vehicle with a sedan or minivan.

Participants expressed a willingness to compromise or even give up some things in the pursuit of fewer fill-ups. More than half of the car owners surveyed said they would compromise on size or capacity with their next car. Not surprisingly, owners of large SUVs were the most open to downsizing, with a smaller SUV or crossover cited as the most likely replacement. About half would give up some amenities or comfort. Survey respondents with household incomes less than $50,000 were more willing to make concessions than more-affluent households.

There were even some respondents willing to give up some performance by going to a smaller engine. Curiously, the CR survey found men were more willing than women to sacrifice engine power.

As can be seen from the chart above, this trend isn’t really new, though it seems to have received a significant amount of media attention during the most recent round of gasoline price increases and the widespread talk of prices hitting $5.00/gallon by summer. Following the end of the American love affair with bigger pickups and excesses like the Hummer and Ford Excursion around 2004, when average fuel economy dropped to a two-decade low of 19.3 miles per gallon, the figure began a steep climb that accelerated after gas hit an all-time record of $4.114/gallon ($4.40 in 2012 dollars) in 2008. In the past six years, the average has increased 3.5 miles per gallon to a record 22.8 mpg.

There is a danger attached to relying on surveys like the Consumer Reports study: First, responses don’t always turn into actions and, second, there is no clear understanding of the word “small.” National Highway Traffic Safety Administration figures show that when it comes time to sign on the dotted line, Americans shun truly small cars in favor of weight, power and acceleration. From 1993 to 2010, the latest year for which figures are available, the average new vehicle gained nearly a quarter-ton of weight and 73 horsepower and shaved 2.3 seconds from its 0-60 time. In fact, the average vehicle sold in 2010 weighed slightly more than it did in 1975. It’s likely the additional 1.6 miles per gallon in fuel efficiency over the past 20 years is attributable more to engineers and designers working to make vehicles more efficient than any major change in consumer buying habits. There was a significant cumulative weight drop from 2008 to 2009, but more than 52 percent of that drop was recouped in 2010 and the NHTSA estimates 2011′s results will show another increase in weight.

When it comes to the American carbuyer’s definition of small, it’s definitely a relative term. Visions of vast numbers of micro-cars are more dream than reality. In April of this year, Ford sold more than four times as many Fusions as it did Fiestas and the Chrysler 300 easily outsold the Honda Fit and Toyota Yaris. Americans are downsizing, but the actual compromises are small, as in giving up the room of an Expedition for an Explorer or an Escape.

Study after study claims Americans are interested in alternative fuel vehicles and hybrids are accounting for a larger portion of total light vehicle sales. But the growth is due almost entirely to Toyota and the market remains small even with a large number of brands and models from which to choose. Manufacturers like Ford and Honda have seen significant declines in hybrid sales. Furthermore, a recent study showed that consumers are unlikely to replace a hybrid with another hybrid. It’s quite possible that new entrants in the market, like the Ford C-Max, which have a lower price-point, will have a positive impact on consumer buying, but that remains to be seen. Diesels are also growing but, in spite of the wide availability of engines available to all the major automakers, only a handful of German manufacturers offer them.

Flex-fuel, for lack of a better term, is a joke, especially for someone looking to economize. Today’s price for unleaded regular gasoline is $3.678 per gallon. E85, a mixture of 85 percent ethanol and 15 percent gasoline, is $3.217 per gallon which looks like a savings of 46.1 cents. The kicker is that ethanol doesn’t contain as much energy as gasoline so one has to buy $4.233 worth of E85 to get the same work as a gallon of unleaded. That 46.1-cent savings is actually a 55.5-cent loss. In addition, ethanol manufacturers haven’t been able to get satisfactory yields from non-food biomass, so they continue to divert large quantities of corn from the food supply, driving up the cost of feeding a family. So flex-fuel is a two-time loser for now.

One special caveat applies to responses from younger drivers. When it comes to “green cars,” they may talk the talk, but they definitely don’t walk the walk. They do tend to buy smaller cars, but there’s not a greenie among the top models purchased by the Millennials.