If you're interested in finding a new or used car that will retain its value, our latest list is for you. We've compiled a listing of used cars that are worth the most after three years, but unlike our list of luxury models, this one caps prices under $40,000 to help budget-minded car shoppers. The data comes from our Trade-In Marketplace tool -- a free AutoTrader.com service that provides you with an immediate cash offer for your used car. But just remember, that means these dollar figures are no-haggle trade-in values, not retail prices.
1. GMC Yukon Denali
With an average Trade-In Marketplace offer of around $39,500, the Yukon Denali tops our list of the highest trade-in values under $40,000. That's no surprise, given the car's traits: aggressive styling, huge size and, most importantly, a luxurious interior that includes features such as a Bose sound system, leather upholstery, ventilated seats and automatic damping suspension. The Yukon Denali is also an excellent tow vehicle thanks to its 403-horsepower 6.2-liter V8 -- a big improvement over the 320-hp 5.3-liter V8 in other Yukon models.
2. GMC Sierra 2500HD Denali
GMC's full-size Sierra HD pickup is now offered in an upscale Denali trim level. And it's no surprise that the high-feature, high-luxury pickup would rank near the top of our list of models under $40,000 with the highest trade-in values. That's because the pickup boasts an impressive 6.6-liter diesel engine, combined with features more commonly found on a luxury car. To us -- and to many shoppers -- the Sierra HD Denali is worth every penny of its $39,100 average trade-in offer.
3. Chevrolet Tahoe LTZ
The Tahoe LTZ is essentially Chevrolet's version of the upscale GMC Yukon Denali. So why does it rank behind the GMC? While its trade-in value of around $38,000 isn't much lower than the Yukon Denali's, the Tahoe LTZ certainly doesn't offer the same cachet as GMC's high-end SUV. That's a factor to shoppers who prefer the allure of the Denali name. But the Tahoe also has GM's 5.3-liter V8 instead of the muscular 6.2 of the Denali. Still, the Tahoe LTZ provides high-level luxury, big-league towing capacity and room for the whole family.
4. Chevrolet Corvette Grand Sport
With other Corvette models undoubtedly ranked higher, the Corvette Grand Sport takes fourth place on our list of vehicles with the top trade-in values under $40,000. The Grand Sport didn't lose much value in three years. From a base price of around $55,000 in 2011, the model's average Trade-In Marketplace offer was just under $38,000 today. That could be chalked up to the fact that most owners don't put high miles on their pricey Corvettes. Either way, the 430-hp Grand Sport is a lot of car for under $40,000.
5. Ford F-250 King Ranch Crew Cab
Where GMC has Denali, Ford has King Ranch. The most upscale variant of Ford's F-250 ranks fifth on our list, with a trade-in value of around $37,600. That's not surprising when you consider everything the F-250 offers, including a 6.7-liter turbodiesel with an almost incredible 800 lb-ft of torque. But the F-250 isn't just a pickup, it's also a luxury car, owing to a long list of standard equipment such as stitched leather upholstery, heated and cooled front seats and Ford's MyFord Touch system with SYNC.
6. Chevrolet Suburban LTZ
Interestingly, trade-in offers on the Chevrolet Suburban LTZ are lower than offers on the smaller Tahoe LTZ. Compare $37,500 for the Suburban to just over $38,000 for the Tahoe. That's a small difference but still noteworthy since the Tahoe is much cheaper when new. Our theory: Many shoppers don't need the Suburban's huge size. But for those who do want space, the Suburban LTZ offers it. Think 3-row seating plus an enormous cargo area capable of hauling luggage for a whole family. Of course, the Suburban also can tow big loads with its muscular 320-hp 5.3-liter V8.
7. GMC Yukon XL Denali
Like the Tahoe and Suburban, the Yukon XL Denali actually ranks lower on our list than the smaller, regular-length Yukon Denali. The gap is even wider with the Yukon: Regular-length models are worth around $39,500, while the XL Denali is closer to $37,500. The reason is likely that most shoppers don't need the extended length body. But if you do need the space, we highly recommend the XL. Few vehicles combine its luxury trimmings, high-end interior and immense 8,000-lb towing capacity.
8. Ford Mustang Shelby GT 500
The Shelby GT 500 sets a high standard for muscle-car performance. It has a raucous 5.4-liter V8 that makes 550 hp -- more than most exotic supercars. Zero-to-60 miles per hour comes in around four seconds, and the sole transmission is a slick 6-speed manual. With such strong performance credentials, it's no surprise the Shelby GT 500 landed in eighth place on our list, earning an average trade-in offer of around $37,300.
9. Ford F-150 Harley Davidson
The F-150 Harley Davidson Edition is a sought-after pickup among truck shoppers and motorcycle riders alike. It combines the practicality of a pickup with the eye-catching allure of a Harley, an appeal that includes exterior graphics, large wheels, chrome accessories and a throaty exhaust. While it isn't everyone's cup of tea, those who like the F-150 Harley Davidson Edition are willing to pay big money for it: The average trade-in value of a 3-year-old model is around $36,600.
10. Ford F-250 Lariat Crew Cab
The Lariat model slots just below the high-end King Ranch in Ford's pickup hierarchy. But that doesn't mean it wants for equipment. On the contrary, the F-250 Lariat boasts a long list of luxury goodies, such as leather upholstery, dual-zone automatic climate control, a Sony sound system and MyFord Touch with SYNC. All that luxury may take your mind off the fact that it's still a truck -- but a truck it is, with a torquey 6.7-liter turbodiesel V8. The result is a trade-in value of around $36,300.
What it means to you: Our list of used cars under $40,000 with the top trade-in values is an eclectic mix of performance, power and utility.