Q: I have a 2006 Toyota RAV4, four-wheel drive with 125,000 miles, in excellent condition. It doesn't have a dipstick for the transmission, which means that it's a sealed system. Is the fluid good for the lifetime of the car? And, if so, what is meant by "lifetime"? I've had Toyotas go over 225,000 miles. Should I have the transmission fluid changed as a precaution? It's kind of pricey at $500-plus.
A: As you have found out, when Toyota says the transmission will last the life of the vehicle, they're thinking of 200,000 miles or more. The only time you need new ATF (automatic transmission fluid) is if there is a failure. And that's not likely.
Motormouth: What's a car's 'lifetime'?
By Bob Weber
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Read the label
Q: After discovering an unfortunate flat the other day, I refilled the tire and bought a can of spray-in leak repair. Before I had a chance to use it, my mechanic flipped, saying that stuff ruins your tire's pressure gauge monitor. Am I lucky that I didn't use it?
A: Every can of tire inflator should say on the product that it is safe for tire pressure monitoring devices. If it doesn't say that, the stuff probably is so old that it should be tossed out.
Mileage quandary
Q: With all the trucks being sold and the reduced number of cars being sold, it seems to me that the EPA required mileage standards cannot be met. Is the standard just a "suggested" target? Is the reduced mileage that is associated with the cold winters in Minnesota and other northern states factored into this standard?
A: Your hunch is right: More new trucks than cars are being sold. (Crossover small utility vehicles had not been counted as trucks in the past.) Corporate average fuel economy (CAFE) standards are set by the government and measured with EPA standardized tests. In cold northern states, your fuel economy may suffer, but the official EPA city/highway figures are still from the standardized test.
The leak won't stop
Q: I own a 2020 Chevrolet Silverado 3500 with a 6.6-liter gas engine. I love the truck but am having an issue with the brake hydro booster dripping fluid. This is after having the hydro booster replaced twice. My longtime mechanic has perused the internet and talked to GM repair staff, but so far nothing has come up to explain this expensive, seemingly endless repair. Hoping you can.
A: Chances are there is a worn seal inside the booster unit. Although some mechanics will go through the trouble to replace the seal, most will opt for a remanufactured unit. Sometimes it helps to pump the brake pedal four or five times before starting the engine. I'm not sure why this helps.
Bob Weber is a writer, mechanic and ASE-certified Master Automobile Technician. His writing has appeared in automotive trade publications, Consumer Guide and Consumers Digest. Send automotive questions along with name and town to motormouth.tribune@gmail.com.
about the writer
Bob Weber
Star Tribune writers showcase Minnesota architecture.