| by Bob Weber | |
(2007-10-31) |
Slap and tick
Q--I have a 2002 Chevy with the 4.2-liter engine. On cold days, it tends to sound "diesel-like" for a few minutes, and then when it warms up the sound goes away. The dealer says this is normal, because the oil bleeds away from the lifters. My owner's manual says 5W-30 is preferred, but that 10W-30 is acceptable down to 0 degrees F. My question is: would a little thicker oil help the "diesel" sound? How about 10W-30 synthetic?
A--It is not that unusual for lifters to drain down over night, and when they do, the make a clicking or ticking noise briefly during the first moments after starting. If the noise is more of a clatter, like the noise a diesel makes, it is probably piston slap. Annoying, but generally harmless. I doubt that switching to different oil would make any difference.
Throw it out
Q--I have a 1993 Chevy Cavalier with a five-speed and 3.1-liter engine. While it is idling in neutral with the clutch is released, I hear noises of moving parts coming from the transmission. I figured that fluid might be low but it was full. Is this a major concern? What could be the problem?
A--The noise you hear may not be coming from your transmission, but from the throw-out bearing (release bearing) for your clutch. After ten years, you are probably due for a clutch job and that includes a new pressure plate, clutch disc, throw-out bearing, and possibly flywheel.
Fast lube experience
Q-- How do you tell when ball joints are bad or going bad? Just what are the "sounds" they make or behaviors that manifest?
A--By the time ball joints start making noise, they are dangerously worn. But before they make a sound, you may notice looseness or play in the steering. It is best to have a professional mechanic examine them whenever you have your next lube and oil change. By the way, the person at a fast lube joint may not have the expertise to do this.
Time to reboot
Q--At the time of my last oil change, the mechanic noted a torn CV boot on the left side and suggested I replace the boot and the axle shaft on my 1993 Acura Legend Coupe. The car has 128k miles.
Immediately following the repair, an audible and palpable vibration presented itself. This vibration is present at idle when in park, worse when in gear (drive or reverse) while at idle, particularly when the brake is also being applied. The vibration is also present whenever the gas is applied during routine driving.
The repair shop double-checked that they performed the repair correctly, and did some research on the matter. They told me this is a common problem on Legends that have axle shafts replaced, and that the fix is to replace the motor and transmission mounts, which costs approximately $1000. Your thoughts?
A--An axle shaft (or half-shaft) problem usually only manifests itself when the vehicle is in motion. The fact that your car shakes while sitting still makes us suspect an engine problem. If there is a miss, for instance, the engine will shake. This will be more noticeable if the motor mounts or transmission mounts are broken. I would take the car to another shop for a second opinion before committing to having them all replaced.
Pedal pushers
Q--I am now the owner of four Toyotas because they are so reliable. I have purchased all of them as used - two Corollas, one Avalon and now a 2002 Camry that I just purchased for my wife. Unfortunately, she will not drive it because the brake pedal has to travel so far to stop the car.
Because it is still under bumper-to-bumper warranty, I took it to the dealer; they replaced the master cylinder and bled the lines. The brake pedal still travels much farther than the other three cars. What do you recommend?
A--I suggest you look into pedal extenders. They are usually installed to keep short people at least ten inches from the steering wheel to prevent airbag injuries, but one could work to "raise" the brake pedal.
Handbraking
Q--When I am parked and I shift the car into reverse, it's difficult to do so. My mechanic says he cleaned the pads and that I should use the hand brake when I park. Do you think this makes a difference? Please let me know what you think the problem might be.
A--I agree that you should use the parking brake (hand brake) whenever you park the car. Unless you do, the transmission tends to jam the parking pawl if the car moves even a slight bit while parked. This makes it hard to shift from park into drive or reverse.
Due to the large volume, Bob Weber is unable to answer most questions sent to The Car Connection each month. Some may be answered directly, where possible, and others will be included in future columns if the topic is deemed interesting. Be sure to include your real name and full address (city, state, province, country, etc.) when sending your questions.
Weber, a self-proclaimed swell guy, is an ASE-Certified Master Automobile Technician, freelance writer and former editor of Super Automotive Service magazine. His column, "Motormouth," appears weekly in the
E-mail Bob your questions atMechanic@thecarconnection.com.
 |
