The federal government this week predicted that the average national price of a gallon of regular gasoline is likely to peak this summer at a point north of $3.60 a gallon and may hit $4 a gallon.

That isn't exactly a shocking prediction -- a gallon of regular in the Los Angeles area already is at $3.73 a gallon, up from $3.28 a year ago.

So how are consumers reacting?

First, they are driving less. In a survey last month of 1,000 adults, about 64 percent said that gas prices have caused them to alter their driving habits, 19 percent said they have cut back their driving enough to affect their daily lives, and 5 percent said they have stopped driving altogether.

In the automotive marketplace, consumers are finally turning to smaller cars with smaller, more fuel-efficient engines.

In March, 40 percent of new vehicles sold had four-cylinder engines, eclipsing sales of six-cylinder and V8 cars and trucks.

Consider the change in fortunes for the Ford Focus and the F-150 pickup.

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Last month, sales of the F-150 fell nearly 24 percent while sales of the Focus rose by 24 percent. The F-series pickup is still atop the overall sales chart, followed by the Chevrolet Silverado. However, six of the remaining eight top-selling vehicles are sedans or compact SUVs that come standard with four-cylinder engines.

The impact on people shopping for smaller new cars this year -- still estimated to be more than 15 million -- is that dealers are likely to be far more stingy when it comes to bargaining.

Part of that tough negotiating stance comes from dealers recognizing that small, economical sedans are hot items. But another factor is that these sedans have far less profit built into them when compared to SUVs and bigger, luxury sedans.

According the consumer shopping site Edmunds.com, a Toyota Corolla LE has a base list price of $16,650 and an invoice price of $15,067, leaving less than $1,600 haggle room for most consumers.

But Edmunds.com says that a Toyota Sequoia SUV, which lists for $35,275, has about $4,000 in negotiating room before hitting the dealer invoice.

That means consumers, who may have become accustomed to seeing thousands knocked out of the window sticker, may have to adjust their expectations.

And if gas prices continue to rise as expected, getting a good deal on a fuel-sipping sedan may be harder to come by.

Here are this week's reader questions:

• Small-car bargains disappearing fast • Do 'teaser rate' car loans exist? • Am I paying too much interest? • Can I get a refund if the motor fails?

If you have a question for Terry, e-mail him at Driving for Dollars. Save money on your car -- sign up for Bankrate's new weekend Car & Money newsletter.