Some used cars are better bets than others.
And just as new hybrid cars vary in efficiency, driving quality, and sales volume, some used hybrids may be a more conservative bet than others.
A used Toyota Prius is by far the most familiar and most numerous hybrid, with more than 7 million sold globally over the last 18 years.
But there are also a growing number of orphan hybrids showing up on used-car lots.
And just because it says "Hybrid" on the badge doesn't mean that it will get particularly good gas mileage or be particularly pleasant to drive.
Perhaps most worrisome, it may also be unfamiliar to your local dealer's service and maintenance staff, because so many hybrid orphans sold in such low numbers.
So here's our expanded list of used hybrids about which you should think twice before signing on the line and digging into your wallet.
[EDITOR'S NOTE: We originally published this article in July 2012, and it proved surprisingly popular. We've gone back and updated it three years later to reflect the latest crop of orphans, substandard performers, and hybrid vehicles that we're just not all that impressed by. Your mileage may vary.]
2011 Volkswagen Touareg HybridEnlarge Photo
2011-2015 Volkswagen Touareg Hybrid
The Touareg is a large SUV that sits at the pricey end of Volkswagen's U.S. lineup. And it's hardly a volume vehicle, with fewer than 7,000 sold in all of 2014.
That means the hybrid version of the Touareg is likely to be rarer yet, most likely no more than 15 percent of that number--and perhaps considerably less, considering that a Touareg TDI diesel model sat next to it on showroom floors.
The powertrain was fairly sophisticated, mind you, with a supercharged 3.0-liter V-6 that puts an electric motor between the engine and VW's eight-speed automatic transmission.
Total power output was 380 horsepower and 428 lb-ft of torque, and all-wheel drive was standard in the U.S.
The hybrid Touareg drove nicely enough in our test, and we certainly liked the same powertrain in its Porsche Cayenne Hybrid incarnation as well.
But we worry that down the road, while the Touareg Hybrid was on sale for five model years, its very low volumes will pose service challenges.
We also note that VW Group is now deemphasizing conventional hybrids and moving to a next generation of more powerful hybrid systems with plug-in capability.
2014 Nissan Pathfinder Hybrid information page on Nissan North America website, Jun 2015Enlarge Photo
2014 Nissan Pathfinder Hybrid
The second addition to our expanded list is a one-year wonder, the unimpressive mild-hybrid version of the Nissan Pathfinder seven-seat SUV.
With its anemic 15-kilowatt (22-horsepower) electric motor sandwiched between a 2.5-liter four-cylinder engine and an adapted version of Nissan's continuously variable transmission (CVT), the hybrid Pathfinder was unable to accelerate on electricity alone.
Instead, its little motor added torque to the engine output and restarted the engine after stops. All well and good, if such systems provide an actual real-world boost in gas mileage over the alternate 3.5-liter V-6 engine.
In our experience, it didn't. And the buying public apparently wasn't very impressed either.
The Pathfinder Hybrid lasted only a single model year before it was withdrawn from the market, making it the definition of hybrid orphan.
We don't know how many were actually sold; Dan Passe, senior communications manager at Nissan North America, said that number of Pathfinder Hybrids was "unfortunately" not available.
Meanwhile, plans for similar mild-hybrid versions of the Nissan Murano and Nissan Rogue crossover utility vehicles seem to have been filed away in the "Never Mind" drawer.
2014 Infiniti QX60 Hybrid - Driven, August 2014Enlarge Photo
2014 Infiniti QX60 Hybrid
Then there's the hybrid version of the QX60 (nee JX), the more luxurious seven-seat crossover from Nissan's luxury brand--which uses exactly the same underpinnings as the Pathfinder Hybrid.
This one too has quietly vanished after a single model year, and we suspect its sales numbers were even lower than those for the hybrid Pathfinder.
Last year, about two and a half times as many Pathfinders were sold as QX60s, so if Pathfinder Hybrids are rare, QX60 Hybrids may fall into the "hen's teeth" category.
We'd still suggest that they're another orphan hybrid to avoid.