KIWI SILVERADO BRAKINGQ: I live in New Zealand and I'm on my third Silverado. My problem is that the front rotors on my 2005 Chevy K1500 Crew Cab overheat. The rotors develop hot spots that are blue. Even under light to moderate braking, they become extremely noisy with heavy vibration. I do a fair amount of towing. This truck has traveled 60,000 miles and I'm already on my third set of brakes, requiring a fourth set. The original set lasted 12,000 miles, then I received an aftermarket set with pads (origin unknown) and they lasted 600 miles, if that. The third set of rotors and pads were supplied out of GM Canada and the same thing happened but took a little longer. I've had the vehicle over a brake machine, to check the pressure differentials between front and rear, and by all accounts they're within the manufacturer's parameters. Should I replace them with drilled and slotted rotors?
A: Why did you replace the rotors every time as opposed to resurfacing them? Also, how much trailer weight are you pulling and cargo weight are you hauling? Exceeding any of the manufacturer's maximum capacities is going to wear out your brakes fast. As a matter of fact, even below the maximum capacities, more weight is always harder on the brakes. Normal lifespan of brakes has always been a gray area due to the variables--not just because of the weight you're lugging, but also the driving habits involved. 12,000 miles on a pair of half-ton front brake pads is considered a short lifespan, but almost within the normal range. When saying the brakes are gone, we mean the front pads are down to the wear indicators and/or only a few millimeters of lining remain. Often a pulsation from the pedal while braking due to warped rotors will appear long before the pads are worn out (you can resurface rotors without replacing the pads). Getting hot spots on the rotors and pads wearing out in only 600 miles (if that's actually the case) tells me there's a major problem that should be obvious to you and/or a capable technician. Either you're drag racing while pulling a house, or there's a significant mechanical failure being missed. You've eliminated front-to-rear brake pressure differential being out of specifications as a problem. So I'd be looking for a continuous drag on the front brakes, or perhaps airflow to the brakes being blocked, be it by custom wheels or forward body modifications.
ELECTRICAL TROUBLESHOOTINGQ: My 5.7-liter 1995 Chevy Silverado 2500's 100-amp alternator has recently been discharging the battery as I drive. I replaced the battery and the alternator, but the problem persists. I checked thoroughly for wires touching the block, but didn't find any. The blinkers, heater, etc. seem to work okay, but the charge gauge continues to go down until the truck finally shuts off. Any ideas where to go from here?
A: Quality varies depending on where you bought the alternator and what you paid for it, so keep the possibility of a defective replacement part in the back of your mind. In the meantime, turn the ignition on and look for the generator light on the instrument cluster. Even though it has a volt gauge, it still has an idiot light. If the charging system is functioning correctly, the indicator will light up with the ignition on, and will go out when the engine is running. If it doesn't light up at all, check fuse #4 in the fuse block on the lower left-hand side of the instrument panel. If the fuse and indicator bulb are good, then there's probably a break somewhere in that circuit, or a bad alternator. This alternator is externally simple with an internal voltage regulator doing the electronic tough stuff. But it has to be cleanly bolted to the engine to provide a good ground, the circuit from the alternator to the generator light has to be working (brown wire, terminal L at the four-terminal alternator connector), and there has to be a complete high-amperage circuit (heavy gauge black and red wire) from the alternator output terminal to the positive side of the battery. A quick way to confirm the alternator's connection to the battery is to remove the output wire from the alternator and check it with a 12-volt test light. If it lights up, you're good. If it doesn't, follow that circuit to the battery and find the break. A likely trouble spot will be the blue fusible link located closer to the battery. The link is a wider section of the alternator output wire with an internal element that burns through under excessively high-amperage conditions (like a regular fuse). Sometimes the outside of a link will look good, but the element is still burned through beneath the insulation. Pull on either side of the fusible link. If it stretches, it's no good. After that, be sure the alternator output circuit has a good connection all the way to the positive battery terminal, both terminals are clean and tight, and the negative side of the battery has solid connections to the engine and the chassis.