I was surprised by what I found.

The plan was to identify those models that had managed to win additional customers without the benefit of costly makeovers. These holdovers can be the most profitable ones for automakers. New cars don't make any money until they've been on the market for several years because they have to amortize engineering, tooling, and launch costs. So instead of just recording the vehicles that recorded the highest percentage sales increases compared with 2011, I weeded out all those models that had been reworked and only looked at carryover models.

I expected my list to be studded by hardy perennials like the Ford F-150 pickup and Toyota Camry. But after some number crunching by the crack statisticians at Edmunds.com, the winners turned out to be mostly older models that had been heavily incentivized to keep drawing customers after the new wore off. More than anything, car buyers like to find a deal.

Here are the 10 models that made the biggest sales gains in 2012 without the benefit of a redesign.

10. Volvo XC60

Up 47%

With familiar boxy Volvo station wagons now extinct, buyers crossed over to the XC 60 that first appeared in the 2010 model year and has become Volvo's most popular model.

9. Honda Ridgeline

Up 51%

Honda's first effort at a pickup doesn't get much respect from dyed-in-the-wool truckers. But despite rumors of its imminent demise, sales of the seven-year-old vehicle increased by half in 2012.

8. Dodge Avenger

Up 55%

Firmly positioned as the price leader among mid-size sedans, Avenger set six monthly or all-time sales records on its way to the Chrysler museum. It is due to be replaced for the 2014 model year.

7. Lexus LX 570

Up 59%

The old-timey body-on-frame SUV hasn't been completely redesigned since 2006, but cosmetics including a new front bumper, grille, headlights, and side mirrors presented a more up-to-date face to customers.

6. Nissan Quest

Up 64%

The fourth-generation version of Nissan's minivan went on sale early in 2011, and fans still love it for its origami-influenced design, upscale interior, and smooth ride.

5. Toyota Land Cruiser

Up 77%

Like the Lexus, Toyota's (TM) Land Cruiser added enough bling to noticeably enlarge its tiny circle of customers (2,579 through November).

4. Smart fortwo

Up 94%

After a slow start, Smart has been adding dealers, and customers are warming to the second-generation model that first came to the U.S. in 2008. A battery-powered version due in spring should give sales a further charge.

3. Chrysler 300

Up 104%

The iconic sedan got a boost from a Consumer Reports review, as well as from younger buyers, who responded to more affordable equipment packages that kept starting prices below $30,000.

2. Kia Rio

Up 111%

The third-generation Rio, introduced in March, 2011, was lifted by a new marketing scheme as well as new TV and Web ads, helping make Kia the U.S.'s seventh-most-popular brand.

1. Chevy Volt

Up 239%

General Motor's (GM) technology showcase/showroom sluggard benefited from price cuts -- as much as $10,000 on the $40,000 car or leases as low as $249 a month -- to more than triple sales. Even the eco-conscious like a deal.