Car Doctor: Any thought as to why the rear-view mirror shakes?
Q: I purchased a 3-year-old Infiniti Q40 four years ago from a dealer. The car had slight cosmetic damage to one wheel and the front rotors, and one of the wheel bearings was replaced in 2018 when the car was first purchased.
At speeds more than 75 miles per hour, the rear-view mirror shakes. The steering wheel does not shake at all and there is no vibration in the car. The tires have been replaced and the wheels rotated and balanced multiple times in the last four years. Any thoughts?
A: The rear-view mirror is picking up a very slight vibration in the car. That vibration could be coming from a wheel, tire, bearing or even the engine.
Since the steering wheel is not vibrating, the issue is more than likely from the rear of the car. These wheels/tires are very finicky to balance and use a special collet, rather than a cone, on the balancing machine.
Since the vibration only happens above the speed limit, it may be easier to live with the issue rather than fix it.
Q: I bought a used 2017 Toyota 4Runner from a dealer. The truck had less than 15,000 miles at the time. Since then, I'm on my third set of front brake rotors, which currently need replacing.
The first time, the dealer replaced the original rotors with aftermarket rotors that didn't work.
Next, the dealer replaced those with dealer-supplied rotors. I only got about six months of driving before the steering wheel started shaking again. We've also been careful about torque when replacing the wheels. Any thoughts?
A: Toyota products are very sensitive to wheel torque and — in Toyota’s words — “even one wheel lug over- or under-tightened can lead to a brake vibration.”
The hub that the rotor slides onto may also be causing the rotors to distort.
Before replacing the rotors again, clean the hubs of any rust and measure for any out-of-round/runout.
Next, check the calipers for proper operation and use a high-quality brake pad.
In some rare instances, if the rear brakes are not working properly, the front brakes will overheat.
One other possibility: If the factory wheels were replaced with larger aftermarket wheels and tires, that could also be causing the rotors to distort.
Q: I have a new-to-me 2016 Buick Cascada. It’s a one-owner car with 80,000 miles. Since purchasing the car in November, I have noticed that the Clear Coat paint is peeling on the front and back bumper sensors, all four of them. The car is garaged when not being driven. I purchased a warranty, but, of course, paint is not covered. I checked for recalls and didn't find any. Do you have any suggestions on how to repair this without replacing both bumpers?
A: The bumpers don’t need replacing but they do need refinishing. A good body shop should be able to sand the clearcoat and respray the bumpers. In some cases, this can be accomplished without removing the bumper covers.
Q: I have a 2010 Dodge Charger with 66,000 miles on it. About six years ago, one of the OEM key fobs stopped working. Then, about three years ago, the second one also stopped. I could start the car, but the doors or trunk could not be unlocked or locked remotely.
I cleaned the contacts and swapped out the batteries with fresh ones, but it didn’t help. I had the fobs reprogrammed. That worked for a while.
I then purchased two new fobs online from an aftermarket (not Dodge) dealer. Both have now stopped working.
I now have four fobs that do not work. I can still start the car but no remote locking or unlocking.
Other than going to the dealer and paying for two new fobs — something I was told will run me about $600, is there anything else you'd recommend?
A: Generally, any Chrysler product manufactured since 2010 requires fob programming to be performed at the dealer or at an automotive locksmith. It is unlikely the fobs failed, but rather they need to be reprogrammed. I would try a locksmith and see if they can test the fob’s transmitter ability and then reprogram the newest fobs.
John Paul is the AAA Northeast Car Doctor. He has more than 40 years of experience in the automobile industry and is an ASE-Certified Master Technician. Write to John Paul, The Car Doctor, at 110 Royal Little Drive, Providence, RI 02904. Or email jpaul@aaanortheast.com and put “Car Doctor” in the subject field. Follow him on Twitter @johnfpaul or on Facebook.
This article originally appeared on The Providence Journal: Why does the rear-view mirror shake above a certain speed?
