• Q. On a recent visit to my home, my “wonderful” mother expanded her range of “helpful” advice-giving to the manner in which I park my car on my steeply sloped driveway. She was deeply concerned about the order in which I engage park and the emergency brake. She advised me that by placing the car in park first and then engaging the emergency brake, I am sure to ruin the transmission. Her motherly recommendation is, of course, to reverse the order, thereby saving the world. I’ve been unable to find either a confirmation or a denial regarding the proper order for my parking procedures. Would the brothers be willing to provide a final word on this matter? Thanks. •
TOM: We’re going to use the worst four words an adult daughter can hear: Your mother is right.
RAY: Well, her instructions are right. She’s wrong about the severity of the consequences, but she is correct that the preferred parking method on a hill is to deploy the parking brake first, to hold the car in place, and then put the transmission in park, to back up the parking brake.
TOM: Here’s why. Park works by using a ratcheting mechanism called the parking pawl to lock the output shaft of the transmission. Because of the way the differential works, locking the output shaft allows the driven wheels to turn only if they move in opposite directions. So unless the car is being dragged or it slides (which ain’t easy if you’re a car), once it’s in park, it’s not going anywhere.
RAY: But because of the way that ratchet system is designed, if you put the car in park and then it rolls up or down a hill a few feet, the weight of the car ends up resting on the parking pawl, pushing it in tighter than it needs to go.
TOM: Will that ruin your transmission? No. But it can make it hard for you to get the car OUT of park when you go to drive away. Maybe you’ve even noticed this.
RAY: This is especially true of older cars, where these parts have started to wear out and create “slop,” or in cars that have been parked incorrectly on hills for many years — like yours! Of course, it matters only on steeper hills.
TOM: By applying the parking brake first, you allow the brakes to do the job of holding the wheels in place, so the car doesn’t roll and push the park mechanism to the point where it’s difficult to remove.
RAY: Then, when you drive away, you do the opposite: You take the car out of park first, and then release the parking brake.
TOM: I know this is a tough blow to absorb. But just remember, this could be a completely isolated case of Mom being right, and have no bearing on whether she also was right about your first three husbands.
• Q. My mechanic found a 4-foot-long boa constrictor in my manifold, in Boonton, N.J. It cost me $310 to get it out. It was barbecued, of course. How the heck did it get in there? •
RAY: Wow. I’m guessing you discovered it because it was affecting your car’s performance. This boa was “constricting” your exhaust, and cutting down on your car’s power. You probably took in the car and innocently asked your mechanic to see what he could find.
TOM: And I just want to give thanks that I wasn’t the guy who found the snake. I definitely would have hit my head on the underside of the hood as I went screaming and running out of the shop!
RAY: There’s only one realistic way the snake could’ve gotten into the exhaust manifold: by going up the exhaust pipe.
TOM: It’s not easy. There are a lot of baffles and obstructions in the muffler and elsewhere. And there’s a honeycomb in the catalytic converter that would have to be broken or crumbling to allow him to get past it. But if anything could work its way up the exhaust pipe, it would be a snake.
RAY: The only other way is through the intake, but that would require the snake to somehow get into AND out of one of the cylinders through the valves, and that’s highly unlikely — even for a talented snake.
TOM: I’m guessing this was a pet that either escaped or some idiot decided he didn’t want anymore. It’s a shame for everybody. Especially that poor mechanic and the snake.
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