AUTONET TV

The Sign of the Shield (Heat Shield Repair and Replacement)

Even in the months where temperatures are cooler, heat is still an enemy of your vehicle.  When your engine runs, it creates heat, so there are numerous heat shields that protect other parts from those higher temperatures. Heat shields are installed around several areas of the exhaust system.  Others prevent heat from reaching parts of the vehicle.  Still others prevent heat from reaching the ground (or maybe grass underneath) and starting a fire. 

If you remember your space travel history, you'll know how important a heat shield can be. John Glenn was the first American to orbit the earth, but during that maiden orbital flight, a sensor on board was indicating the heat shield on his capsule, Friendship 7, was loose.  If it had come off, his spacecraft could have burned up upon re-entry.  Fortunately, the heat shield stayed on, and Glenn made history.

Unfortunately, the heat shields on your vehicle don't have warning systems like the space vehicles did.  So you have to maintain them.  Heat shields are constantly exposed to elements like water, salt, sand and dirt.  That makes them prone to rusting and corroding.  Here's one unfortunate fact: Materials that make them good at preventing heat transmission also are soft and vulnerable, often aluminum or special fabric. 

One sign a heat shield will give you that it's loose is noise; you'll sometimes hear it rattling underneath your vehicle when it's running. One way to locate it? Put your vehicle in park, leave the engine running and take a listen outside.  It's usually pretty easy to pinpoint the location.

Make a note of the noise when you are talking with your service advisor. It's important to have those heat shields working correctly so the heat is kept away from your other vehicle systems and combustibles on the ground. The good news is that heat shields can frequently be inexpensively repaired or re-attached.  In other cases, they should be replaced. 

Missing or loose heat shields? Let's just say they're not cool.

A.G. Automotive & Diagnosis
19735 Sherman Way Suite 2
Winnetka, CA 91306
(818) 438-9608
http://www.agautodiagnosis.com

In That Case? (Transfer Case Exchange)

Ever wonder how all-wheel-drive or 4-wheel-drive vehicles get the power from the engine to the front and rear wheels? The magic happens in what's called a transfer case.  In some all-wheel-drive vehicles, it's sometime called a power take-off unit, or PTU.

Inside the transfer case is a set of gears.  And to keep those gears meshing smoothly, they have to be lubricated and kept cool.  What does that is called transfer case fluid. Depending on your vehicle's type of transfer case, it is filled with either an automatic transmission fluid, a gear oil that's a bit thicker or transfer case fluid designed to be use for your transfer case.

As happens with all lubricating fluids, the transfer case fluid has things in it that break down the older they get.  They have corrosion inhibitors, detergents and anti-foaming agents that keep the lubricant from getting air bubbles in it. Transfer cases don't have filters in them to clean out impurities.

If you don't have your transfer case fluid exchanged for fresh, you risk damage to the case, and that can run into thousands of dollars.  So the wise driver makes sure the fluid is changed according to the manufacturer's recommendations.  For many vehicles, that is every 30,000 mi/50,000 km, but some require it more frequently.   Your vehicle service facility can advise you on what your vehicle's optimal interval is.

During the fluid exchange, any metal filings that may have come off are cleaned off of the drain and fill plugs that are usually magnetized to catch the stray metal pieces.

If you hear grinding noises coming from under your vehicle or if it is having trouble shifting gears or going in and out of 4-wheel-drive, those could be signs your transfer case needs service. In that case, have our technicians check it out.  The best plan of action?  Keep your transfer case fluid maintained and it should keep you heading down the road for years to come.

A.G. Automotive & Diagnosis
19735 Sherman Way Suite 2
Winnetka, CA 91306
(818) 438-9608
http://www.agautodiagnosis.com

Stop It! You Need Good Brakes

Good brakes are obviously very important. If you've ever had your brakes go out while you're driving around the Winnetka area, you'll know how terrifying it can be. Today we'll focus on how to tell when you have a brake problem and how to make good repair choices.

Often, the first indication that something's wrong with the brakes is an unusual sound. It could be a squeal, chatter or grinding sound.

Some brake pads have a little piece of metal embedded in them that will make a squeal or chirping sound when the brake pads have been worn down to the point that they need to be replaced. It's an early warning indicator.

When you hear that sound, schedule an appointment at A.G. Automotive & Diagnosis soon.

Now a chattering sound is more urgent. That usually indicates that something is loose. It could be a brake pad or even the brake calipers. If one of those parts falls off, you could have some serious trouble stopping the vehicle. It would be a good idea to park it until you can get into the shop.

A grinding noise usually means that the brake pad is completely worn away and the metal parts of the brake are rubbing directly on the metal brake rotor. That means the rotor is being damaged and will need some work. More on that later.

Another warning sign is that your brake pedal may feel soft and spongy – or it may even feel very hard to push in. Both could mean trouble. And of course, you may get a dashboard brake warning light.

Now when it comes time to replace your brake pads, you have a choice to make. You can get the same pads that came standard on your vehicle. You can expect the same performance and durability as with the pads that came on the car from the factory.

Now you can also get a budget brake pad. Sometimes Winnetka drivers insist on lower cost pads. That's OK if the budget demands it, but you need to be aware of the tradeoffs. Lower grade pads are usually noisier, so you'll have to live with more noise when you apply the brakes. They also tend to generate a lot more brake dust, you know, that black dust that accumulates on your wheels. And they probably won't last as long either. In our opinion, that's a lot of compromise for just a few dollars in savings.

You can also choose to buy premium brakes pads at A.G. Automotive & Diagnosis. These perform at higher specifications than the factory pads. You can expect quieter operation, less brake dust and better stopping power.

Now, getting back to the rotors. The rotors are the discs that the brake pads clamp down on to stop the vehicle. If you've been driving with completely worn brake pads, you've scratched grooves into the rotors. If the grooves aren't too deep, the rotor can be resurfaced. A thin layer of metal is cut off the surface of the rotor to make it smooth again.

Now, if the grooves are too deep or if the rotor has already be resurfaced before, there may not be enough material to resurface and still have a rotor that's thick enough to safely stop the vehicle. In that case, the rotor will have to be replaced.

Something that's often overlooked is the brake fluid. Your manufacturer has a recommended schedule for evacuating the old brake fluid, cleaning the system and refilling it with fresh brake fluid. This is really important to brake performance.

So here's the bottom line: if you suspect, inspect. If you notice any of these warning signs, have your brakes inspected at A.G. Automotive & Diagnosis in Winnetka. Your service advisor can help you make the repair decision that's right for you.

A.G. Automotive & Diagnosis
19735 Sherman Way Suite 2
Winnetka, CA 91306
(818) 438-9608
http://www.agautodiagnosis.com

Power Steering Service in Winnetka

Most Winnetka drivers are too young to remember life before power steering - cranking those great big steering wheels! It was a pretty good workout. Now power steering is standard. Let's look at how it works. The heart of any power steering system is its pump. The pump pressurizes the power steering fluid that provides assist for steering. Most pumps are driven by a belt that is run by the engine; a few are electrically powered. A high-pressure hose passes fluid from the pump to the steering gear. A low pressure hose returns the fluid back to the pump.

These hoses can develop leaks, so it is a good idea for Winnetka drivers to have them inspected at every oil change. Low fluid can damage the power steering pump. That is why power steering fluid level is on the checklist for a full-service oil change. The fluid needs to be compatible with the hoses and seals, so check your owner's manual for the right type - or just ask your friendly and knowledgeable pros at A.G. Automotive & Diagnosis in Winnetka.

The fluid cleans, cools and lubricates the power steering system. It breaks down as the years go by and collects unwanted moisture, so Winnetka drivers need to replace it from time to time. Many vehicle manufacturers specify power steering service intervals. Unfortunately, this important service is sometimes left off the car maintenance schedule for many of us. So, when in doubt, every 25,000 miles/40,000 km or two years is a good fallback. Your technician at A.G. Automotive & Diagnosis will use a detergent to clean the system, flush out the old fluid and replace it with the good stuff.

Here are some  warning signs of trouble with your power steering: It's harder to turn the wheel, there's erratic power assist, you hear loud whining coming from the pump (which may be difficult to hear over the loud whining coming from the backseat), you have to top-off the fluid frequently, or you hear squealing belts. Remember to never hold the steering wheel to the far right or left for more than a few seconds at a time. That will wear out your power steering pump quickly.

Other steering components can be bent or damaged from wear or hard knocks: ball-joint, idler-arm, steering-gear, steering-knuckle and tie rod to name a few. Warning signs here are steering play, wandering, uneven tire wear and an off-center steering wheel. An annual alignment check at A.G. Automotive & Diagnosis in Winnetka will reveal bent or damaged steering components.

Most SUV's, pick-ups and rear-wheel-drive cars need regular front-wheel-bearing service.

The bearings should be cleaned and inspected. If they are excessively worn, they need to be replaced. The bearings are then repacked in clean grease. The team at A.G. Automotive & Diagnosis also recommends the wheel-seal be replaced when the bearings are serviced. Like everything else, check your owners' manual maintenance schedule. It's usually required around every two years or 40,000 miles/64,000 km. If you drive through water in the Winnetka area, the bearings will need service more often.

A.G. Automotive & Diagnosis
19735 Sherman Way Suite 2
Winnetka, CA 91306
(818) 438-9608
http://www.agautodiagnosis.com