Q: I would like your opinion on the advantages of 4WD vs. FWD vehicles. I loved my first front-wheel-drive vehicle, an early ’80s Chevy Citation, and the traction it provided in icy/snowy conditions. I have a steep driveway and have never been unable to make it into the garage despite the weather. In fact, I have never been stuck driving in snowy conditions in urban and suburban areas. Since 4WD vehicles cost more, are heavier and tire diameter is more of a problem, I don’t ever plan to own one. What’s your opinion?

A: The real question is this: Do you need 4WD or do you want 4WD? You’ve described the reality of “needing” 4WD in urban/suburban areas. Unless you’re the plow truck or ambulance driver and positively have to get to work before the roads are cleared or you spend a significant amount of time driving off-road, you probably don’t need 4WD.

We’ve had our 4WD Tahoe for 20 years and I can count the number of times I “needed” 4WD on both hands — and this in light of me having to be at the TV station at 4:30 a.m. to do morning traffic reports, no matter the weather. But I “wanted” 4WD available to deal with the rare situations when it provided a real benefit. Thus, it was worth it to me.

Yes, there’s a higher purchase price and efficiency cost in the extra weight and drag of the 4WD components — lower miles per gallon. But before writing off 4WD, compare the resale value of a 4WD vehicle vs. a FWD vehicle, particularly if it’s a truck or SUV.

Which is why I think the best overall choice is AWD — all-wheel drive. But that discussion is for another column.

 

Q: I have a brake problem on my 2004 Saab 9-3 with 2-liter turbo engine. The power assist is not working and I have to use excessive pressure on the brake pedal to stop. I’ve searched everywhere for info, including the Clymer shop manual. Other than identifying that the power assist is partially done by vacuum and a gear at the end of the camshaft, it was no help.

 

A: Much help is available on the Internet. My ALLDATA database pulled up several Saab service bulletins and even a recall dealing with this issue. The recall in 2005, which may have included your vehicle, identified potential failure of the vacuum pipe to the power brake vacuum booster.

The most likely cause for the lack of power assist is this pipe or the check valve at the booster. A more significant issue would be a problem with the camshaft-driven vacuum pump not supplying vacuum to the booster. Because the engine is turbocharged, a vacuum pump is necessary to supply adequate vacuum to assist the brakes.

 

Q: We have a 2000 Chrysler Town & Country with about 135,000 miles. The brake warning light will come on occasionally while driving and then go off. What should I check to solve this problem?

 

A: Assuming you are talking about the brake warning light on the dash, there are three things to check. First, the fluid level in the brake master cylinder. If it is low, the warning light will illuminate. Secondly, excessive brake pedal travel travel due to a loss of pressure in the system will trigger the light. Thirdly, a stuck parking brake mechanism can leave the warning light illuminated.

Don’t take this signal lightly — it indicates a potentially serious safety issue with the brakes.