Q: I'm having a recurring problem with my 2013 Chevy Impala with 31,000 miles on it. I'll go for months without any occurrences, then it may happen five times in one week. It's a loud, scraping, grinding noise that lasts only a second or two and is coming from the left front tire area. The noise is similar to ABS kicking in during a slide. It happens after I've backed out of my driveway or parking spot and I'm starting to go forward. Since it happens so quick I haven't noticed any messages or warning lights on the dash. There's no evidence of tires scraping in the wheel well and it doesn't sound like a drum/rotor screech. Does this sound like an impending safety issue?
A: You may well be hearing the initialization process of the EBCM — the electronic brake control module. Once per ignition cycle the EBCM activates the module's solenoids to ensure proper operation and readiness. The quick initialization will occur during one of two circumstances — when the EBCM detects at least 500 rpm and the brake pedal is not applied or vehicle speed is more than 10 mph and the brakes are applied. The initialization will sound and feel like ABS activation because that's exactly what it is.
Since the noise appears to specifically be originating in the left front, check the wires and connections for the left front wheel speed sensor. Anything — water, frayed wires, debris, etc. — interrupting the signal from this sensor may cause the ABS to activate. It might be worth having a scan tool check for EBCM fault codes.
Q: I am the original owner of a 1996 Ford Ranger with the 4-liter engine and 305,000 miles. I change the oil every 5,000 miles and the engine does not burn oil. Amazing. The owner's manual does not address timing chain replacement. What are the chances I can get another 100,000 miles out of the engine without experiencing failure of the original timing chain?
A: The 4-liter V-6 in your Ranger is fitted with a steel roller timing chain, not a rubber/fabric belt. No maintenance is required nor is there a replacement interval recommended. In most cases, timing chains are "life of the engine" components. At 305,000 miles your "life of the engine" is exceptional and reflects excellent preventive maintenance and a conservative driving style. Will you get another 100,000 miles from the engine? No one can predict or guarantee engine life, but with such high mileage almost any significant mechanical failure would likely be "end of life" for the vehicle, much less the engine.
A worn timing chain or gears will tend to begin making noise well before complete failure. As the chain and gears wear, more and more slack develops in the chain. This can lead to the chain rubbing on the inside of the timing cover, generating a distinctive rattling sound. A mechanic's stethoscope or long rod pressed against the timing cover — with all due safety and care — can readily confirm worn timing components needing replacement.
Congrats on the amazing mileage you gotten from your Ranger. Keep doing what you've been doing and hopefully you'll see 400,000 on the odometer someday.
Q: I have a 2005 Dodge Dakota with 55,000 miles on it. The tires are original, with good tread. I'm wondering if I should replace the tires due to their age. What about the spare? It has never been on the truck.
A: As long as you see no signs of weather-checking on the sidewalls or any other visual issues, the tires would appear to be serviceable. However, if the remaining tread depth is less than 4/32nds to 5/32nds of an inch, it's time for new tires. Leave the spare as the spare. Even if you purchase the exact same tires as replacement, the difference in age and date of manufacture likely make the spare a poor match for new tires.
Paul Brand is the author of "How to Repair Your Car" and "How to Repair Your Truck and SUV," published by Motorbooks.