Q: Do you recommend the installation of an after-market blind-spot sensor? It would go on a 2012 Camry. If so, what are recommended brands and who installs them?

D.A., LeSueur, Minn.

A: If you have an older car, or one that was not equipped with a blind-spot sensor, an aftermarket kit may be the answer. But — and this is a big but — they are expensive. Low-priced units cost around $200-$300 while the better ones are in the $500 range. Experts say that none are as good as the factory-installed ones, but the pricier ones come close. Coming close is what you want to avoid with another vehicle, too. If you have not yet won the lottery, there are inexpensive, stick-on blind spot mirrors.

Q: I want to respond to the tire sealant problems. About a year ago I was coming back from Cape Cod and in the trunk of my car I had a large explosion. At the next truck stop I discovered that a full can of tire sealant had exploded in my trunk. What a mess: sticky, gooey foam everywhere on our luggage, clothing and gifts. Do you have any ideas on how to prevent this in the future? I love to carry that stuff because it’s a lifesaver, but I don’t want to go through anything like that again. You have to warn people that the can says do not store above 120 degrees and I guess my trunk was much higher than that.

F.S., Chicago

A: Some tire sealant products are under pressure to help inflate the tire while sealing. Other products are not under pressure but need an auxiliary pump to finish the job. Many carmakers are losing the spare tire and substituting a kit containing a sealant and a pump that plugs into the car’s 12-volt auxiliary (cigarette lighter) port. Sorry to hear about your messy experience. Did you get everything clean? One more thought: Check with your insurance carrier as this accident may be covered under the comprehensive coverage.

Q: I read your column reference to tire sealer for vehicles with no spare tire. A good subject for a future column would be tire sealers. I recall seeing in tire repair shops that they would not repair a tire if tire sealer had been used as a temporary repair. Perhaps tire sealing products have improved?

A.T., Chicago

A: Actually, many tire technicians would rather not work on a tire that has goo in it. Most of the products remain liquid or gel. It coats the inside of the tire and the rim. Both must be cleaned before the tire can be professionally, and permanently, patched. Even with a new tire, the rim must first be cleaned. Yuck. “Hey Timmy, I’ve got a job for you.”

Q: I noticed the segment about the swollen lug nuts in a recent Motormouth column. On two occasions I have had to replace lug bolts on our 2014 Subaru Forester. The tire guy at Cassidy Tire suspected a supplier had used “soft steel” (his term) for the lug bolts. (The service rep at the dealership declined to comment.) Regardless, it’s an expensive fix and there’s not much the owner can do when the car is up on the rack, the wheel is off and there’s no way to put it back on without replacing the stripped lug bolt.

J.C., Chicago

A: There is plenty of anecdotal evidence of Subaru lug stud (not called a bolt) breakage. I don’t know the underlying reason. My suggestion is to avoid replacing the damaged studs with factory (Subaru) studs. I have confidence in Dorman brand products, especially their fasteners.

———

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.

Send questions along with name and town to Motormouth, Rides, Chicago Tribune, 435 N. Michigan Ave., Fourth Floor, Chicago, IL 60611 or motormouth.tribun