Buy a car, get gas money

This post comes from Kelli B. Grant at partner site SmartMoney.

As anxiety over the price of regular unleaded intensifies, more dealerships are topping off deals on new cars with free gas cards.

The latest ad from Seeger Toyota in St. Louis offers "100 free gallons of gas" at $4 per gallon -- $400 total -- with the purchase of a new Prius. Titus-Will Chevrolet in Tacoma, Wash., offered $500 Safeway cards to drivers buying a Silverado, Suburban, Tahoe or Traverse.

Even used cars have incentives. Last month, A&T Chevrolet in Sellersville, Pa., began offering printout coupons redeemable for special pricing and a $200 WaWa conventience store card for models like a 2007 Jeep Patriot and a more fuel-efficient 2009 Nissan Altima. "We tried it out to distinguish ourselves from other dealerships," says general sales manager Earl Walton. (Post continues below.)

Gas card deals frequently pop up when prices rise, but this year experts say that for some models, these incentives may be the only cash deals buyers see. Industrywide, rebates averaged $2,193 in February, down 14.5% compared with the previous year, reports Edmunds.com.

"People think $4 gas and they look back at 2008 when there were insane auto deals," says Ivan Drury, a senior analyst for Edmunds. But automakers are better prepared now for high gas prices: March sales are projected to be significantly better than last year, and they would represent the best monthly tally since before the recession.

Automakers have also limited their supply of gas-guzzling models and introduced more fuel-efficient options, which gives them pricing leverage, says Kristen Andersson, a senior analyst for TrueCar.com. "We're just not seeing these big cash-back incentives," she says.

Although $500 worth of gas can be enticing, drivers should consider such offers only after shopping around for the best price, Andersson says. Many gas card offers are available only on vehicles purchased at sticker price or the dealership's posted rate -- which means no haggling.

If there are no rebates available, she says, negotiating can still drop the price by $1,000 or more. Even people hunting for a popular Toyota Prius can shave 2% off by shopping around, netting a discount of nearly $500.

Some offers are good only on purchases made from the dealer's existing inventory, which could limit selection to less-popular models and options packages. Gas card deals are typically also restricted to a particular station. That may be less valuable if that station has among the highest prices in an area, or if it isn't near the driver's home. And even $500 doesn't equate to that many fill-ups as gas prices continue to climb.

• MSN Autos:Find the cheapest gas near you

"Every time in the past that we've seen those, it doesn't draw in as many people as you think," Drury says.

But dealerships say they do see more interest when there's pain at the pump. Champion Toyota, Scion of Corpus Christi, Texas, has offered a $100 gas card for the past two years, and Internet sales manager Victor Lara says the number of people bringing in the printable coupon jumped in tandem with fuel prices.

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Shoppers in the market for a large vehicle or luxury auto may be better served by waiting until later this spring, Drury says. Incentives are likely to increase as consumers focus more on fuel-efficient models. Mazda, for example, recently offered $3,000 cash back on its CX-7 SUVs, and 0% financing for 60 months. Ram layered $2,000 cash with bonus offers of up to an additional $2,500 on select configurations of its 1500 Laramie Quad Cab truck.

Consumers looking for smaller, fuel-efficient models may find better deals with 0% financing, too, as the credit market continues to loosen.

More from SmartMoney and MSN Money:

• How to get gas for $2
  4 upsides to high gas prices
• Fewer incentives for fuel-efficient cars
• Calculator: How much vehicle can you afford?
• How to shop smart at a used car lot
• The most and least expensive cars to insure