Q. I own two cars with CVTs (continually variable transmissions. One is a 2011 Nissan Maxima bought used “off lease” from an independent car dealer and a 2017 Honda CR-V (1.5L 4cyl., Touring model – bought new from a Honda dealer). I have read that CVTs can last only half as long as traditional transmissions. The Maxima is nearing 100,000 miles, where (supposedly) CVTs can start to exhibit warning signs of failure. I would like to know: what your professional opinion is on CVTs in general, what I should be aware of with these two particular types of CVTs and finally what kind of preventive maintenance I should be doing to “keep the CVTs happy and fully functional.
A. The earlier CVT were quite problematic, and the newer units are much better. That being said I’m a fan of gears (maybe a generational thing). My experience has been that the CVTs that are problematic were an issue earlier on in the car’s life. I have seen the Nissan CVTs last several hundred thousand miles and as little as 50,000 miles. If you drive normally the fluid doesn’t have a required change interval. If you tow a trailer or drive your Nissan aggressively then change the fluid every 60,000 miles and only use Nissan fluid. On the Honda, just let the maintenance minder tell you when the fluid needs changing. As good as Honda vehicles are, their automatic transmissions were problematic in earlier years and that is why in my opinion, they may have switched to the CVT or the 9/10 speed conventional automatic transmissions in the larger vehicles. A failing CVT will hesitate, shake and vibrate and are quite sensitive to low fluid level issues. Any transmission leaks should be repaired as soon as possible.
Q. I recently read about one of your readers with odd electrical issues and thought I would share mine. My 2016 Audi S4 does occasionally react oddly when passing under the toll gantry at the lower level of the George Washington Bridge. Crossing under the gantry causes my windshield wipers to sweep across the windshield once or twice. I take the bridge on my way home from work, so this is a trip I take often. I am nonplussed by the fact that this doesn’t happen every time I make the trip but have no idea why it happens at all. I consider it to be another one of life’s lesser mysteries.
A. This is referred to as a “phantom wipe” and it is common in many vehicles of all manufacturers. And like many of life’s mysteries, this one does not seem to have an answer. If it truly bothers you, you can change the wipers from auto to off.
Q. My 2011 Honda Accord, with only 83,500 miles, has leaks in the power steering return line. I was told that the whole front carriage would have to be “dropped” in order to reach these hoses. All maintenance has been performed at this dealership, but this type of repair is radical at over $2500 since the dealer also wants to replace the entire steering gear. I don’t know if I can trust that the frame will be safe to drive if the carriage is dropped and reinstalled. It’s like remaking the car Honda explained that these leaks occur because the car is 12 years old. Is it necessary to “drop the front carriage” or could a “stop the leak” solution fix the problems? Will the car be safe to drive after the carriage is reinstalled by the mechanics as opposed to the manufacturer?
A. I think it is time for a second opinion. If the issue is just the power steering line(s) are leaking, then they can be replaced without removing/lowering the subframe. If the steering gear is leaking, then the subframe needs to be lowered to gain access. This is a common repair procedure and completely safe.
Q. Could you please discuss run-flat tires. I have a 2024 NX 350 Lexus that is equipped with them. I think many readers would appreciate learning about this as I believe many new cars have or will have them.
A. Run flat tires are exactly what they sound like. You can drive for a limited distance (50 miles at speeds no greater than 50 MPH) with no air due to the very stiff sidewall. There are a couple of issues, they tend to ride hard and may not be repairable-varies by manufacturer. Years back when evaluating a new vehicle, I could tell which cars had run-flat tires due to the stiff ride. Today the ride has improved, still stiff, but much improved. If these tires are on a sports car, or all-wheel drive vehicle then you may end up replacing at least two tires or maybe even four tires due to one unrepairable run-flat tire, so cost is a factor. Call me old fashioned by I like a spare tire, any kind of a spare tire!
Q. I am planning on buying a 2022 Infiniti Q50, it is a certified preowned model. Looking at the Carfax it appears the powertrain control module was replaced at 8500 miles and it is on the lot with 9300 miles. The car also had a coolant temperature sensor replaced and the rear brakes. Given the car’s age and low milage are these “red-flags”?
A. I looked and there is no common problem with that module. My concern is that whatever prompted the change didn’t fix the problem and that is why the car was traded soon after the repair. That car, like many uses a low and highspeed communications network and there have been several bulletins about the CAN network and repair strategies. Is it a good car to buy, it may be but without knowing the complete repair history it is hard to say. My inclination would be to keep looking.
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