• Q. I have a 2005 Subaru WRX STI with 106,000 miles, and it is time to replace the timing belt. The Subaru dealer will do the job for $1,800, but I found an independent garage that will do the job for $650. The difference is that the dealer would use genuine Subaru parts. The independent mechanic says his parts come from Japan and are just as good as the genuine parts. Should I spend the extra money for the genuine parts, or can I save my money? I would like the car to last another five years, but my finances aren’t that great right now. Please help! Thank you.•

TOM: We normally would use genuine parts in a situation like this, because on this job, the difference in our cost for the parts probably is $100. But I wouldn’t be afraid to use good aftermarket parts on a car with more than 100,000 miles on it. They’d probably be fine. In fact, sometimes they’re the exact same parts.

RAY: But since the difference in the parts price is small, there has to be something else to explain why the dealer’s price is triple the independent mechanic’s.

TOM: Like, he’s got a bigger boat he’s trying to pay off.

RAY: Could be. But it also could be that these two shops have different definitions of the term “timing belt change.”

TOM: For instance, when we replace a timing belt, we always replace the water pump, too. Why? Because the water pump is run by the timing belt. And if the water pump were to seize up a week after you got the timing belt replaced, you’d need, what? Another new timing belt. And wouldn’t that tick you off?

RAY: When the timing belt is already off, most of the labor to change the water pump is already done. So you’re not adding much more than the cost of the part: the water pump itself. And with 100,000 miles on a car, you’d be crazy not to put in a new water pump while you have access to it.

TOM: On a car like this, that has double overhead cams, we’d also take off all the sprockets and replace all four cam seals while the belt is off. Why? First of all, they’re as old as the belt, and you have easy access to them while the timing belt is off. And second, if one of them leaks two months from now, the customer’s going to try to blame us. So we avoid that potential conflict by making it part of the job.

RAY: If we were doing a job like this, on your car the price probably would be somewhere around $1,200. So the Subaru dealer may be charging too much, but the other guy may be charging too little — because he’s not doing enough.

TOM: So, get a better accounting from each of these shops as to exactly what it proposes to do. I’m guessing the dealer plans to do all the stuff we usually do. But check. And you need to find out what, exactly, the other guy plans to do for $650. You also can ask him to give you a price with a new water pump, four new cam seals, a crank seal and genuine parts (if you’re curious).

RAY: Then you can make a fair comparison of the prices and decide whether the real difference in cost is large enough to stay away from the dealer. It very well may be, but you can’t know that unless you’re comparing apples to apples. Or cam seals to cam seals.

•Q. My uncle owns a 2001 Lincoln Town Car. A few days ago we had a real bad storm, and the tree that was about 7 to 10 feet away from the car was hit by lightning. The bolt grazed the tree and hit down on the ground on a root that was only 4 feet from the car. After the lightning hit, we found the headlights on. We were unable to turn the headlights off using the switch. We had to disconnect the battery cables in order to get the headlights off. Could the car have been hit by lightning also? How would we be able to find out if the car actually was struck by lightning?•

TOM: How can you tell if your car has been hit by lightning? Well, if the headlights are permanently fused in the “on” position, that’s a good indicator.

RAY: Or if you start discovering, during the next few days and weeks, that other electronic components no longer function, or function incorrectly.

TOM: Or if there’s a huge pile of charred steel and smoke where the car used to be. That’s a hint that even my brother would pick up on.

RAY: I don’t think your uncle’s car took a direct hit, but obviously there was some high voltage very close to the car. My guess is that somehow, the headlight relay got energized, and its contacts melted and fused together, so it could not be disengaged by the switch.

TOM: I’d guess that replacing the headlight relay will allow you to operate the headlights normally again. The question is, Was anything else affected?

RAY: The worst-case scenario (other than the above-mentioned charred heap of smoking steel) is that the voltage surge fried your computer and some wiring harnesses. That would keep the car from running at all, and would be expensive to repair.

TOM: But there are plenty of other, smaller, insults that can be caused by proximate lightning. So have Unc test all of his lights, blinkers, accessories, etc. And make sure he can still get the Frank Sinatra station on his AM radio (we know 2001 Town Cars come hardwired to that station from the factory). Good luck!

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