Q: A friend of mine just bought a 2002 Corvette. Nice car but he neglected to check out the lug nuts. The wheels have a locking lug nut on each one. There is no master unlock and previous owner is not answering his calls. Any idea on how to go about getting them off without wrecking things?
J. F., Chicago
A: There are ways to remove the locking nuts. Many professional technicians know how to do it. Of course, they will be damaged beyond repair so your friend will have to buy a new set of locking nuts that will include the proper key. The other option is to take his chances with standard lug nuts.
Q: Regarding jake brakes, they are designed for the retardation of vehicle speed when on a down grade. There is no reason, other than to save regular brake linings, for their use if there is no danger of the vehicle over-revving and the driver losing control of the vehicle. They are remarkable safety accessories when used as designed. The use of engine retarders on the flat is the sign of a lazy, cheap, non-maintenance focused, driver. Pick one or all of the above. It's like the driver who uses the trailer brakes to stop the vehicle. In many cases, the trailer belongs to someone else. Unfortunately, not many traffic enforcement vehicles come with audio monitors, and the duration of use is short.
B.S., Lincolnshire, Ill.
A: In town or a residential area, they are also a source of noise pollution.
Q: For reference, a muffler was developed to quiet jake brakes. It was offered with a guarantee to pay any tickets resulting from using jake brakes in no engine braking zones. The truckers were generally not interested. They enjoy the engine brake noise much like the Harley riders like their unique sound.
D.G., St Paul, Minn.
A: I hear you.
Q: I drive a 2017 Acura MDX and the owner's manual specifies that 91 octane fuel is "recommended." The sales staff tells me that mid-grade (89 octane) or even regular grade (87 octane) is acceptable. I've used mid-grade for two years and the engine and performance is good. How does the engine determine the octane level and how does it internally adjust to fuel that is lower than the recommended grade?
K.K., Schaumburg, Ill.
A: With spirited driving, engine knock can occur, so the preferred fuel is one with a higher octane. Under less spirited driving, engine knock is less likely, so mid-grade or regular gas is fine. Continued engine knocking will cause damage, so a knock sensor screwed onto the engine reports the first signs of knock to the engine control module that then backs off the ignition timing until the knocking stops.
Q: We have a 2010 Toyota Highlander with 58,000 miles. On my last couple visits to the dealer for routine maintenance, they have recommended an engine de-sludge. We have kept up with oil changes and other maintenance at the recommended intervals. Is this something modern vehicles need or are they just trying to get me for another $170?
S. M., Skokie, Ill.
A: They are de-sludging your wallet. Select this service if your bulging billfold is bothering you.
ABOUT THE WRITER
Bob Weber is a writer and mechanic who became an ASE-certified Master Automobile Technician in 1976. He maintains this status by seeking certification every five years. Weber's work appears in professional trade magazines and other consumer publications. His writing also appears in automotive trade publications, Consumer Guide and Consumers Digest.
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