Q: After looking at vehicles for my teenage boy and girl to replace the family's high-mileage Dodge Durango, I'm down to the 2007 Honda Pilot and 2008 Jeep Liberty. I also considered a Saturn Vue, but my 17-year-old son feels its body style is more for girls than guys. Finally, should I buy new or used? --D.S., Chicago

A: It's almost a coin toss between the Pilot and Liberty. The mid-size Pilot is a sure bet. The compact, rugged new Liberty gets its first redesign since its introduction and promises to be more fun for teens. Both vehicles have a bunch of safety items. The compact Vue, which also has plenty of safety features, is fun to drive because it's derived from General Motors' European Opel Antara, which is hardly "more for girls."

As for new or used, buy new if you can afford it, although a low-mileage vehicle that looks and drives good and has a documented maintenance history is a fairly safe option -- if checked by a thorough mechanic. Factory certified used vehicles give you a leg up because dealers only offer ones that were above-average to being with. Even then, be prepared to spend some money on any used vehicle.

Q: I can't get my 1997 Range Rover's headlight washers to turn on. Also, a "fault" light recently came on in this vehicle. --M.T., Chicago

A: Headlight washers are a good idea but aren't common on American cars or foreign autos sold in this country. The problem with them is probably being caused by a defective timer switch. As for the light, have a mechanic check out the Range Rover's trouble codes.

Q: What's with the new special color Mercedes-Benz model I hear about? --E.H., Evanston

A: The car has special Obsidian black metallic paint and a custom sahara beige and black leather interior. Mercedes has designed it to raise funds for Saks Fifth Avenue's Key to the Cure women's cancer initiative. Mercedes expects to donate $1 million through the sale of 1,000 of these exclusive C-Class vehicles, now on sale at Mercedes dealerships.

Q: Many Chicago Northwest Side streets are loaded with speed bumps and stop signs at every corner. Is constant stop-and-go caused by those signs and continual bumping caused by the speed bumps hurting vehicles? We realize the signs and bumps are designed to slow traffic, but many folks drive SUVs in our neighborhood so they have no problem going over the bumps -- and they blow right through stop signs. There's also lots of double-parking, although there are plenty of parking spots on the other side of the street or down the block. --W.D., Chicago

A: Speed bumps tend to prematurely wear out suspension components, even on SUVs, and lots of stop signs are hard on brakes and waste gasoline because they cause excessive stop-and-go driving. I've observed that an excessive number of stops signs cause motorists living in the area where they're located to either slow and not stop, or use "Hollywood stops," which mean they glide slowly past the signs without coming to a complete stop. As for double-parking, it's just dumb because it leads to auto body scrapes and dents. But I've seen people double-park rather than walk a block out of their way.

Q: Why does Toyota hardly advertise its 2008 Scion xB body model? How easy is it for an elderly person to get in and out of that vehicle? --J.W., Wonder Lake

A: The new larger, more powerful xB for 2008 (May 7 AutoTimes) is aimed at a young crowd, so Toyota does much advertising for it on the Internet and also uses offbeat promotions for it to prevent young motorists from thinking it's too "commercial" a vehicle. Actually, a fair number of the first-generation xBs were bought by older people who liked its roominess and such things as its high fuel economy and parking ease. It's also easy for older folks to enter or leave it.

Q: Should I have the spark plugs changed in my 2002 Mercury Sable V-6, which has been driven 70,000 miles? Also, my mechanic says its suspension's ball joints have a little play in them, although the car steers well and its tires aren't wearing unevenly. --J.W., Romeoville

A: I'd change the plugs if they are the original ones because (not to pun) they've lost some of their spark. As for the ball joints, leave them alone. But watch for changes in the car's steering and handling.

Car question? Send it to Dan Jedlicka, Chicago Sun-Times, 350 N. Orleans, Chicago 60654, or e-mail djedlicka@ suntimes.com. Include name and hometown.