Dear Tom and Ray: I have an '89 Toyota Camry, which I maintain in good condition. It has 96,000 miles. At my last oil change, my mechanic, whom I trust, wrote, "Found oil leaks: distributor O-ring, valve-cover gasket, front crankshaft seal, rear crankshaft seal, oil pump seal." He said none of this was needed immediately, but he suggested I do the rear crankshaft seal first. I don't see any oil on the driveway or any place else, and I'm thinking of waiting until I do. Does that make sense to you guys?
Tom: Yes. I would recommend that you do nothing, Mary -- with one exception.
Ray: I would have the crankcase ventilation system checked. If the crankcase isn't venting properly, pressure could be building up inside the engine, and that could be what's forcing oil to leak from all of these places -- and some places you've probably never heard of before.
Tom: But if the crankcase ventilation system is working, I'd sit tight on the oil leaks themselves. In 15 years of working on Camrys, I've never had to replace a rear crankshaft seal. So I wouldn't go racing to put in a new one. That doesn't mean that you won't have to replace yours someday, but it could just as well hold on for the life of the car.
Ray: What you should do is check your oil level on a regular basis. Start by checking it once a month, and see how much is actually leaking out. I'd say if you still have the car when you start losing a quart every 500 miles or so, then you can ask your mechanic to take another look and consider fixing the worst of the leaks.
Tom: But until then, I'd say leave the leaks alone. A lot can happen to a car with 96,000 miles on it, so don't plan too far ahead. The engine could blow, the transmission could self-destruct, or you could even be abducted by aliens interested in the longevity of Japanese cars. And if you were abducted by aliens next summer, wouldn't you be miffed that you just put $400 into a rear engine seal?
Dear Tom and Ray: This question is so simple that you've probably been asked it a million times. What happens to all the rubber that wears off of our tires? You never see it, but it's got to be somewhere.
Ray: That's a very good question, Mike. And we didn't know the answer. So we went to the high priests of automotive/scientific knowledge, the Society of Automotive Engineers. You know what? They thought it was a very good question, too. And they didn't know the answer.
Tom: So then we asked the Rubber Division of the American Chemical Society. They also thought it was a very good question. And, you guessed it, they didn't know the answer, either.
Ray: While none of these lofty scientific organizations actually knew the answer, they all had theories, of course! And the universal consensus among all of these esteemed scientists is that the "rubbed-off rubber" is entirely broken down by the sun and air. It's broken down into its molecular parts -- carbon, nitrogen and some sulfur.
Tom: That stuff is then blown into the air and exists as "suspended particles." That's scientific notation for "dust." Obviously, the carbon and sulfur contribute somewhat to airborne pollution, but how much, and whether the amount is at all significant, we don't know.
Ray: This theory was arrived at by process of elimination. There have been people over the years who have suggested that the rubber doesn't break down, but instead builds up indefinitely by the side of the road. But if that were the case, according to Bill Whoerle, tire expert at the SAE, "We'd be plowing rubber instead of snow."
A real spare
Dear Tom and Ray: I just bought a 1996 Subaru Legacy Outback Wagon. This is an all-wheel-drive wagon that comes with one of those stupid little Dunkin' Donuts mini-spares instead of a full-size spare tire. I've heard that if you have to use the mini-spare, you're supposed to disengage the all-wheel-drive so you don't mess it up. Is there any reason (besides money) that I shouldn't just buy another 15-inch rim and stow a full-size spare in the back?
Tom: There's no reason you can't do that, Dave. But personally, I don't think it's necessary.
Ray: You do want to avoid using a mini-spare in all-wheel-drive mode, because using one smaller tire could damage the center differential. But taking this car out of AWD mode is a piece of cake.
Tom: To put the car in "front-wheel-drive-only" mode, all you have to do is insert a fuse. The procedure is described in your owner's manual, and it's really very simple.
Ray: Plus, the mini-spare is not stupid, in my opinion. It may look flimsy (OK, it is flimsy), but it's really quite adequate for emergencies. It's good for about 50 miles, which is enough to get most people home, or to a gas station, or both.
Tom: If you live out in the boonies and often find yourself more than 50 miles from civilization, then it makes sense to have a full-size spare. But for most people, it's just not necessary. And besides, flat tires are becoming rarer and rarer these days due to significant improvements in tire quality.
Ray: Then there's the issue of room. While many cars have room for a full-size spare, some do not. I don't remember whether or not the '96 Legacy has a full-sized-spare-tire well, but check before you buy a wheel and tire -- or you may wind up with a permanent tire-sculpture-art installation in your cargo area.