Q: I own a 2004 Saturn Ion but my questions are about automatic transmissions in general. If you are coasting towards a stop light and shift the transmission into neutral, will this slow the car down? Also, will this hurt the transmission? My other question is: If you are still coasting along and the stop light goes green, then you shift the back into "Drive," will this hurt the transmission? -- D.C., New Lenox

A: D.C., shifting from drive to neutral while coasting won't hurt the transmission. However, while coasting in neutral, no engine braking will occur. Engine braking is desired when approaching a stop or coasting down a hill. Plus, once you want to begin accelerating again, shifting back into drive with the vehicle in motion is not good to do on a regular basis. Once in a while, such as if the engine stalls while driving, is okay. But I wouldn't want to make a habit of it. That's because engagement of the proper gear while moving will likely occur with greater force than it normally does and this can cause excess wear inside the transmission. I also would not recommend shifting into neutral at a stop and then shifting back into drive to take off. Every time you shift from neutral to drive, a mechanism is shifted from a released position into an applied position. It's better to leave the shifter in drive and keep everything applied, ready for acceleration. Considering the expense of rebuilding an automatic transmission, and considering that it's designed to be operated without shifting, I'd recommend leaving the shifter in drive.

Q: I own a 2003 Buick Regal with about 38,000 miles. I want to get an oil change in about a month or so, but it's down about half a quart. There's no oil on the ground and I don't think it could be burning oil because it runs like new. I'm just wondering if you know what might be causing the oil to be half a quart low. -- M.A., Oak Forest

A: M.A., if the oil level was full at your last oil change and it's down half a quart, it had to go somewhere. If it's not leaking, it has to be consuming. It's normal to consume/burn a small amount. G.M. says that provided the PCV system is functioning normally, the engine should consume no more than one quart per two thousand miles. At that rate, the oil consumption will not cause any drivability concerns either. So, I wouldn't be too concerned about being a half quart low. Just keep a watchful eye on it and be concerned if and when the consumption exceeds one quart per two thousand miles.

Q: I own a 2000 Pontiac Bonneville SSEi with about 102,000 miles. Due to handling problems, the suspension system components like strut mounts, control arms and bushings have needed replacement recently and it has cost me about $2,000. I think this is a bit excessive for a vehicle with this kind of mileage. What do you think? -- V.A., Homewood

A: V.A., if all of those miles were on perfectly flat roads with no potholes, I'd be concerned. But I'm willing to bet a fair percentage of those miles were over pothole-infested roads. There are many factors that shorten the life of suspension components. Here's a list of some of them: poor road conditions, high-speed driving and cornering, tire/wheel imbalance, poor wheel alignment, and carrying heavy loads and/or trailer towing.

Questions for Ira Siegel? Call the Auto Adviser Hotline at 708/633-6839 or e-mail Autoadvisr@aol.comAutoAdviser: Ira Siegel is an Automotive Instructor and ASE Certified Master Auto Technician