QDear Tom and Ray:

I have a grandson who was born three months premature. At his current rate of growth, he'll be in a rear-facing car seat when he goes to his senior prom. When I'm driving, I hate not being able to see how he's doing back there. I also have an 8-year-old granddaughter. She doesn't weigh enough to sit in the front seat with me. I feel like buying a chauffeur's hat. Since road noise interferes with my hearing, we don't talk much. Are there sound, logical, research-based reasons for my grandkids being banished to the back seat?

-- John

ARAY: I know how you feel. When we were kids, I had to stand in the back of the car, because there wasn't room for me to sit down. My brother, my sister and my grandma took up the whole back seat.

TOM: We had no seat belts, and the dashboards were metal. And nobody worried about him standing back there.

RAY: I guess I was lucky, and now we know a lot more about safety. The recommendations for transporting kids are to put all kids under 12 in the back seat. Infants under 20 pounds go in a rear-facing child seat. And once they're a year old and more than 20 pounds, you can put them in a forward-facing child seat.

TOM: Where did these guidelines come from? From a large amount of unfortunate crash history. The recommendations are issued by the National Highway Traffic Safety Administration. The reason for the rear-facing child seat is that pediatricians concluded that an infant's neck simply can't take the stress in a crash, and the neck will snap. So the back of the seat is needed to support the neck.

RAY: And at the age of a year, and at 20 pounds or so, they think most kids' muscles and bones are strong enough to handle a restrained, forward-facing crash without their necks snapping.

TOM: Many years of crash history have shown that kids are safer in the back seat, where they're farther away from the windshield and any penetration by the engine or other components in a front-end crash. Plus, with dual front air bags now mandatory (22 kids have been killed by air bags in rear-facing child seats in the front seat), you don't want a little kid where he or she can get killed by an exploding air bag.

Dear Tom and Ray:

I can't convince my wife that the chattering produced by her '99 Chevy Cavalier (30,000 miles, lots of brake pad left) when it rains is normal. I point out that the intermittent braking noise (only when wet) stops after you lightly ride the brakes to dry them, but she feels that catastrophe can be averted only by paying an "expert" for his sage advice. Can you help me here?

-- Dave

RAY: Well, your wife might have very good reasons for discounting your diagnosis.

TOM: For instance, what if your last diagnosis was "just the tire rubbing against the wheel well, hon" but it turned out to be a bad ball joint, the wheel fell off and your wife drove into a vegetable cart.

RAY: But you might be right. Drum brakes are notorious for "grabbing" when they're wet. So if this car has drums in the rear, they could be grabbing the first time you stop. And the chattering you hear is the anti-lock brake system kicking in to keep the rear wheels from locking up.

TOM: So if you have drum brakes in the rear and this only happens the first time you drive the car after a rain, then chances are you're right, Dave.

RAY: But if it happens more often than that, or if you have disc brakes in the back (which was an option on this car), then I think it's worth taking the car to the dealer and having the brakes checked and the ABS sensors scanned.

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(c)2002 by Tom and Ray Magliozzi

and Doug Berman