Auto Education

Why Cars Need Preventive Maintenance?

My Check Engine Light is On, What Should I Do?

How Often Should Oil & Filter be Changed?

What Type of Motor Oil is Recommended for My Car?

What are the Significant Causes of Excessive Tire Wear?

What Does a Complete Tune-Up Include?

High Mileage Vehicle Inspection and Maintenance

What Are the Recommendations for Changing Filters?

What Kind of Maintenance is Recommended for the Cooling System?

What is Included in a Complete Brake Job?

Exhaust Systems Guide

Why Cars Need Preventive Maintenance?

Manufacturers know that a properly maintained car will be more dependable, safer, owners also have a responsibility to make sure emission controls receive regular service and are functioning properly. Regular maintenance helps accomplish these goals by keeping your engine running efficiently and eliminating potential problems that may leave you stranded.

What's in it for you?

* More Dependable Car
* A car that retains the "new car feel"
* Less chance of a costly breakdown
* A safer car for you and your family
* Doing your part for cleaner air
* A car worth more at trade in or sale
* An intact warranty

Manufacturer Maintenance Schedules

The manufacturer creates detailed maintenance schedules outlining specific operations to be performed on various components and systems. This is done at different mileage intervals to ensure proper operation and prevent premature wear. The manufacturer also indicates what services must be done to maintain the factory warranty and extended warranty.

______________________________________________________________________________________________________

Check Engine Light

When the ignition switch is initially turned on and the engine is not running, the malfunction indicator lamp lights for a bulb check. While the engine is running, the MIL will light only if there is an emissions-related concern.

The on board diagnostic (OBD) generation two (II) system continuously monitors all engine and transmission sensors and actuators looking for electrical faults, as well operating conditions are met and a comprehensive monitor detects a failure that will result in emissions exceeding a predetermined level, the computer stores a diagnostic trouble code, and illuminates the MIL.

The OBD II system also actively tests some systems for proper operation while the vehicle is being driven. Fuel control and engine misfire are checked continuously, catalyst efficiency, exhaust gas recirculation operation, evaporative system integrity, oxygen sensor response, and the oxygen sensor heaters are tested once per trip when prerequisite operating conditions are met. The computer will illuminate the MIL if during these prerequisite operating conditions the system detects a failure that will result in emissions exceeding a predetermined level.

Whenever an engine misfire severe enough to damage the catalytic converter is detected, the MIL will blink on and off.

Once lit, the MIL will remain on until the vehicle has completed three consecutive good trips (three trips in which the fault is not detected). The MIL is also turned OFF when stored diagnostic trouble codes are cleared. However, the MIL will only remain OFF if the fault is successfully repaired.

______________________________________________________________________________________________________

 

How Often Should Oil & Filter be Changed?

Change oil and filter often enough to protect the engine from premature wear and viscosity breakdown. For most cars and light trucks, the standard recommendation is to change oil and filter every six months or 3,000 miles, whichever comes first.

Most late model owner's manuals say that except for "Severe Service" applications, oil change interval can be safely stretched to once a year or every 7,500 miles, with filter changes at every other oil change.

When auto makers make such recommendations, one assumes they are based on extensive durability testing. After all, auto makers themselves would have to bear the warranty costs should their maintenance recommendations prove inadequate.

Except for Chrysler's 7/70 powertrain warranty, and a few others that go up to 5/50 or 6/60, most new car powertrain warranties don't go beyond 3/36. So where's the risk? There isn't any.

With proper maintenance, there is no reason an engine shouldn't go 100,000 miles or more without developing a thirst for oil. That is why most oil companies, as well as aftermarket service professionals, recommend changing oil and filter every six months or 3,000 miles.

They also make such recommendations because many motorists are not aware that they should follow the "Severe Service" maintenance schedule in their owner's manual, calling for oil and filter change intervals of three to six months or 3,000 miles. Severe service (as defined by auto makers themselves) includes:

• Making frequent short trips (less than five miles)
  
• Making frequent short trips (less than 10 miles) when temperatures are below freezing
  
• Driving in hot weather stop-and-go traffic
  
• Driving at sustained high speeds during hot weather
  
• Towing a trailer
  
• Driving in areas with heavy dust (gravel roads, construction zones, etc.)
  
• Extensive idling and/or low speed driving for long periods of time (taxi, police, door-to-door delivery, etc.)
  

 

Protective additives in a motor oil do not hold up as well under such driving conditions for several reasons. If the engine is not running long enough to get the oil hot, condensation and fuel vapors will not boil off. Contaminants will accumulate in the crankcase, leading to formation of corrosive acids and sludge.

Excessive idling and high operating temperatures from towing and high speed driving during hot weather accelerate viscosity breakdown. Exposure to dust can put dirt particles in the crankcase.

The filter also needs to be changed every time for two reasons. Today's pint-sized filters do not contain as much filter material as their quart-sized counterparts. The filter contains dirty oil that can contaminate fresh oil added during an oil change.

Considering what four quarts of oil and a filter cost, versus the cost of replacing an engine, it is better to change oil and filter a little more often than might be absolutely necessary rather than risk not changing it often enough.

______________________________________________________________________________________________________

 

What Type of Motor Oil is Recommended?

Use the type of motor oil specified in your customer's owner’s manual. Most manuals say it's okay to use a variety of viscosity grades depending on temperature conditions. Generally speaking, the following holds true:

• 10W-30 is best for all engines for year-round driving. 10W-40 is more popular in the aftermarket, but 10W-30 is actually a better oil because the additive package in it holds up better over the long haul. This is why General Motors does not recommend 10W-40 motor oils for any of its cars.
  

• 5W-30 is approved for most late-model four-cylinder, V-6 and V-8 engines on a year-round basis. It is not approved for many turbocharged or diesel applications, some high output V-8s, or applications involving driving at sustained highway speeds or towing in hot weather. It may not be the best choice for older, high mileage engines.
  

• 5W-30 is used as the factory fill oil on most new cars because it pumps through the engine more quickly after start-up (important for keeping overhead cams properly lubed). It also makes cold weather starting easier and reduces fuel consumption.
  

• Straight viscosity oils have limited temperature ranges and lack the versatility of multiviscosity oils. They can be safely used as long as their temperature limits are observed.
  

• Straight 10W is okay for cold weather starting and driving, but too thin for warm weather driving.
  

• Straight 20W is okay for all around driving, but doesn't provide the temperature protection of straight 30W (which gets too thick at low temperatures for easy cold starting).
  

• Straight 40W and 50W oils are primarily for heavy-duty applications.
  

• Special multiviscosity oils such as 2OW-50 are typically formulated for racing or severe duty applications such as towing.
  

• Synthetics are a good alternative for any of the above because most provide extended temperature protection and service life.

______________________________________________________________________________________________________

 

What are the Significant Causes of Excessive Tire Wear?

Uneven or accelerated tire wear can be caused by wheel misalignment, worn suspension and steering components, and/or improper tire inflation.The most critical alignment angle with respect to tire wear is toe. Camber is also important and can be affected by caster. Misalignment is usually caused by worn, loose or bent suspension and steering parts (bad tie rod ends, idler arms, control arm bushings, ball joints, struts, etc.), but can also be due to spring sag or improper ride height.

With tire inflation, under-inflation is just as bad as over-inflation. Both can cause uneven tire wear. Under-inflation can also make a tire run dangerously hot.

For a tire to roll down the road with the least amount of resistance and maximum directional stability, it must be aligned with the road, parallel to the other three wheels on the vehicle, square with the chassis, and properly inflated.

Rolling resistance is affected by a number of things, one of which is the straightness of the tire with respect to the direction of travel. If the tire is skewed slightly to one side or the other (toed in or out), it will scrub as it rolls. Scrub increases rolling resistance and also wears away the tread, leaving a feathered wear pattern.

Toe refers to the parallelism of a front or rear wheel to its companion on the opposite side. From a bird's-eye view, all four wheels should be parallel to one another and pointing straight ahead.

Toe is measured by comparing the distance between the front edges of both tires on an axle to the distance between the trailing edges. If the distance between the front edge is further apart than that at the rear, wheels have toe-out.

If front is closer together than rear, wheels have toe-in. Toe settings may be specified in inches, millimeters or degrees. Toe is most affected by worn tie rod ends, a worn or loose idle arm or center link, or a bent steering arm.To minimize tire wear, rolling toe should be kept as near zero as possible. To achieve this, the compliance or amount of give in the vehicle's steering linkage and suspension must be taken into consideration.

As a vehicle starts to move, rolling resistance pushes the tires back. This compresses the couplings and rubber fittings in the steering linkage and causes the wheels to toe-out slightly. It isn't much of a change, but most rear-wheel drive vehicles call for static toe-in settings of around 1/16" to 1/8" to compensate.

With front-wheel drive, the situation is different because the front wheels pull the vehicle down the road. Engine torque causes the wheels to toe-in under load. Most FWD suspensions have a negative scrub radius built into the steering geometry.The tire pivots slightly to the outside of its centerline. This helps to offset the tendency to toe-in. Even so, most front-wheel drive vehicles still require toe settings of zero to 1/8" toe out.

Toe also changes as the front wheels turn. Because the inner and outer wheels don't follow the same path (the inner one follows a smaller circle than the outer one), the inner wheel must toe-out to compensate. This is called the "Ackerman Principle of Steering" after the engineer who invented the idea.

Toe-out depends on the angle of the steering arms with respect to the steering knuckles and chassis. The amount by which toe changes is called "toe-out on turns." This angle is also listed in alignment specs and is checked by turning the wheels on the alignment rack.

If toe-out on turns is off because of a bent steering arm, the tires will squeal and scrub whenever the wheels are steered.

Camber also affects tire wear. For directional stability, the tires must be perpendicular (straight up and down) with respect to the road. Any tilt to the inside or outside will cause a tire to turn in that direction like a bicycle leaning into a turn. This causes steering to pull to one side and creates uneven wear across the tread face.

Camber is the inward or outward tilt of the wheels as viewed from either front or rear of the car. If wheels lean in, they have negative camber. If they lean out, they have positive camber.

The amount of camber is always expressed in degrees and is found by measuring the tilt of the wheels on an alignment rack or by using a level that attaches to the wheel.

Because camber affects tire wear, the ideal situation is to have zero running camber on all four wheels to maintain full tread contact with the road. Like toe, camber changes as the suspension moves up and down. To keep the wheels vertical once the vehicle is loaded, a small amount of static positive camber may be required.

Camber should generally be within 1/2 degree side-to-side. Otherwise, the vehicle will lean toward the side with the most positive camber.

Camber misalignment can be caused by a sagging spring, a bent strut, bent spindle, worn control arm bushing, worn ball joint, or mis-located strut tower (too far in or out).

Camber corrections are made by replacing worn parts and/or by realigning the suspension using either the factory adjustments (cams, shims or elongated holes) or aftermarket aids.

______________________________________________________________________________________________________

What Should a Complete Tune-Up Include?

• Electronic ignition, computerized engine controls, and electronic fuel injection have eliminated many adjustments that were once part of a "traditional" tune-up. Most would agree that a tune-up today is a preventive maintenance service and engine performance check.
  
• Call it what you will, a complete tune-up should combine elements of preventive maintenance, adjustment and performance analysis. One of the main reasons people bring a vehicle in for a tune-up is because they are experiencing some kind of driveability problem.
  
• Things like hard starting, stalling, hesitation, misfiring, poor fuel economy, or lack of power are seldom cured by a new set of spark plugs and a few turns of a screwdriver. Every tune-up should include a comprehensive performance check to verify that no driveability problems or trouble codes exist.
  
• Another item that should be included is an emissions check. Thirty-five states now have some type of annual vehicle emissions inspection program, and all but two include a tailpipe emissions check. Most mechanics will check EGR valve operation, the PCV valve, and make a visual inspection of other emission control components and plumbing. But unless an actual emissions performance check is made at the tailpipe, there is no way to know whether or not the vehicle will meet applicable emission standards. An emissions check is a must.
  
• Taking into account longer service intervals and reduced maintenance requirements of today's vehicles, a tune-up is probably only necessary every 30,000 miles, or once every two to three years. This is altered when a driveability or emissions problem arises that requires diagnosis and repair.
  
• The best guide to tune-up frequency is probably the recommended spark plug replacement interval in a vehicle's owner’s manual.
  
• Our list of items that should be included in a "complete" tune-up include:
  
• Replace spark plugs
  
• Replace rotor
  
• Check distributor cap (replace if necessary)
  
• Check timing (adjust if necessary)
  
• Check ignition wires (replace if necessary)
  
• Check ignition performance (firing voltage and ignition patterns)
  
• Check idle speed (adjust if necessary)
  
• Check choke (carbureted engines)
  
• Clean fuel injectors
  
• Check compression and/or power balance (identifies bad fuel injectors as well as compression problems)
  
• Check manifold intake vacuum (reveals exhaust restrictions)
  
• Check battery/charging voltage
  
• Check exhaust emissions (verifies fuel mixture, ignition performance and emissions performance)
  
• Check vehicle computer for trouble codes
  
• Install new air filter
  
• Replace fuel filter
  
• Replace PCV valve
  
• Check all emission controls (EGR valve, air pump, etc.)
  
• Check all vital fluid levels (engine oil, transmission fluid, coolant, brakes, power steering)
  
• Check belts and hoses
  
• Check safety items such as lights, wipers, tires (including inflation pressure), horn, etc.

______________________________________________________________________________________________________

High Mileage Vehicle Inspection & Maintenance

Fixing Your Present Vehicle Saves Money

Most of us want to get the most for our motoring dollar. One of the best ways to do this is extending the life of your current vehicle. With new car prices in the United States averaging well over $10,000, money invested in keeping your existing vehicle in good shape could save you hundreds--even thousands--of dollars a year. When you consider the true cost of buying a new car (price of the car, sales tax, license and registration fees, insurance), it is not difficult to justify investing a few hundred dollars to repair your present vehicle.

Safety and Scheduled Maintenance

The safety aspect of properly maintaining your vehicle, especially when it has high mileage, should not be overlooked. Failing brakes, exhaust leaks and other problems can be prevented by following sound car care practices.

Unfortunately, most manufacturers only provide maintenance guidelines for the first 100,000 miles or so. Clear procedures for maintenance beyond this mileage do not exist. At best, manufacturers provide interval service schedules, such as every 15,000 miles. These schedules should be followed whenever possible. By doing so, you can reasonably expect thousands more satisfactory miles from your vehicle.

High Mileage Inspection and Evaluation

If your vehicle has passed the 100,000 mile mark and you want to significantly prolong its useful life, it is time to have it thoroughly evaluated by a professional automotive technician who can recommend needed repairs or service. This facility is equipped to perform this service. We employ technicians who use factory-level information detailing your vehicle's service requirements.

Our high mileage inspection and evaluation goes beyond cursory "once-overs" and is designed to get to the root of potential problems. Ask your service advisor or technician to show you exactly what is involved in this service. He or she will be happy to go over the evaluation form with you before you okay the inspection and provide you with a comprehensive estimate for any work recommended as a result of your vehicle's checkup. They will tell you about repairs that are necessary today, and also alert you to items that are potential problem areas you may want to address today for more trouble-free miles tomorrow. Naturally, you make the
decision as to what work is actually performed.

Working together, we can add years to the life of your car or truck.

______________________________________________________________________________________________________

What are the Recommendations for Changing Filters?

It is best to follow the Severe Service maintenance schedules found in most new car owner's manuals, with a few exceptions:

• Air filters need to be inspected regularly and replaced as often as needed, regardless of mileage or time. Dirty air filters can increase fuel consumption and exhaust emissions.
  

• Fuel filters should be replaced yearly and/or at every tune-up, especially on fuel injected cars. The fuel filter in a vehicle with electronic fuel injection passes a much larger volume of fuel than its counterpart in a carbureted application. If the tank is dirty or rusty, constant fuel recirculation can pick up a lot of debris that ends up in the filter. If the filter plugs, the engine is starved
  for fuel or unfiltered fuel is allowed to bypass the filter. The latter can damage injectors.
  

• Oil filters need to be replaced at every oil change (every six months or 3,000 miles in most cases) despite the advice in many owner's manuals to only change the filter at every other oil change. A new filter is cheap insurance against major engine damage, so why take unnecessary risks?
  

• Few owner's manuals have a suggested change interval for the automatic transmission fluid (ATF) or fluid filter unless the vehicle is used for towing. Most transmission specialists say the best preventative maintenance for prolonging automatic transmission life is to change fluid and filter every two years or 30,000 miles.
  

• Follow the manufacturer's recommendations on the specific type of ATF to use. The type of ATF should match the specs required for the application.
  

• All GMs, most late model Chryslers and many imports use Dexron II. All 1988 and later Fords require Mercon ATF. Most universal ATF fluids are acceptable for either of these. Older Fords or imports require Type F fluid.

______________________________________________________________________________________________________

What Type of Service is Recommended for the Cooling system?

Replacing coolant on a regular basis will prolong the life of the radiator and other cooling system components. Most new car maintenance schedules call for coolant that too long and recommend every two years or 24,000 miles.

There are some who argue that annual coolant changes on late model vehicles with bi-metal engines (aluminum heads/iron blocks) and/or aluminum radiators is a good idea.

It does not really make much difference how often the coolant is changed as long as it is changed before losing its corrosion resistance. Antifreeze is made of ethylene glycol (which never wears out) and various additives (which do wear out).

Some additives provide "reserve alkalinity" to neutralize internal corrosion before it can start. As long as the coolant is changed before its reserve alkalinity is depleted, can be expensive internal corrosion in the radiator, heater core and engine.

How can you tell when it is time to change the coolant? The only way to know if the coolant still has adequate corrosion protection is to test it. By dipping a test strip in the coolant and noting its color change, you can determine coolant condition and whether or not it is time to replace it.

When coolant is changed, the system should be reverse flushed rather than simply drained. This helps dislodge and remove accumulated debris and debris in the system. It also removes old coolant that would otherwise remain in the engine block.

Use of a cooling system cleaner is not necessary unless the system has been badly neglected and is full of lime deposits.

The cooling system should be refilled with a 50/50 mixture of ethylene glycol antifreeze and clean water. This provides freezing protection down to -34 degrees F and boil-over protection to 265 degrees F.

When coolant is changed, inspect belts and hoses. Make a visual inspection for leaks. Pressure test radiator and cap. Check operation of heater and defroster.

The thermostat does not need changing unless it has been causing trouble or the engine has severely overheated. If a thermostat is replaced, it should have the same temperature rating as the original. This is extremely important on late model vehicles with computerized engine controls. Fuel, ignition and emission functions are all affected by coolant temperature.

______________________________________________________________________________________________________

What is Included in a Complete Brake Job?

A complete brake job should restore the vehicle's brake system and braking performance to good-as-new condition. Anything less would be an incomplete brakemileage and wear. There is no pat answer as to which items need replacing and which ones don't. It's a judgment call.

A complete brake job should begin with a thorough inspection of the entire brake system; lining condition, rotors and drums, calipers and wheel cylinders, brake hardware, hoses, lines, and master cylinder.

Any hoses that are found to be age cracked, chaffed, swollen, or leaking must be replaced. Make sure the replacement hose has the same type of end fittings (double-flared or ISO) as the original. Don't intermix fitting types.

Steel lines that are leaking, kinked, badly corroded, or damaged must also be replaced. For steel brake lines, use only approved steel tubing with double-flared or ISO flare ends.

A leaking caliper or wheel cylinder needs to be rebuilt or replaced. The same applies to a caliper that is frozen (look for uneven pad wear), damaged or badly corroded.

Leaks at the master cylinder or a brake pedal that gradually sinks to the floor tells you that the master cylinder needs replacing.

The rotors and drums need to be inspected for wear, heat cracks, warpage, or other damage. Unless they are in perfect condition, they should always be resurfaced before new linings are installed. If worn too thin, replace them.

Rust, heat, and age have a detrimental effect on many hardware components. It's a good idea to replace some of these parts when the brakes are relined. On disc brakes, new mounting pins and bushings are recommended for floating-style calipers. High temperature synthetic or silicone brake grease (never ordinary chassis grease) should be used to lubricate caliper pins and caliper contact points.

On drum brakes. shoe retaining clips and return springs should be replaced. Self-adjusters should be replaced if they are corroded or frozen. Use brake grease to lubricate self-adjusters and raised points on brake backing plates where shoes make contact.

Wheel bearings should be part of a complete brake job on most rear-wheel drive vehicles and some front-wheel drive cars. Unless bearings are sealed, they need to be cleaned, inspected, repacked with wheel bearing grease (new grease seals are a must), and properly adjusted.

As a rule, tapered roller bearings are not preloaded. Finger tight is usually recommended. Ball wheel bearings usually require pre-loading.

As a final step, old brake fluid should always be replaced with fresh fluid.

______________________________________________________________________________________________________

Exhaust Systems

The longevity of muffler and pipes depends on what kind of steel the components are made of, how pipes are routed under the car, where the muffler is located, and whether or not the vehicle has a catalytic converter.

Original equipment pipes made of aluminumized steel generally last five to seven years, except in areas with a lot of road salt and moisture. In these areas, pipes may need replacing after three to five years.

Original equipment pipes made of stainless steel (which are used from the converter forward on most cars and for the entire exhaust system on some) can last
up to 10 years or more.

Most aftermarket pipes, by comparison, are made of ordinary steel which is good for about three to five years of service. Aluminumized and stainless pipes are better, but cost more.

With mufflers, stainless holds up the best, followed by doublesided galvanized steel. Single-sided galvanized and aluminumized hold up fairly well, while plain
steel offers little or no corrosion resistance.

As a rule, the hotter a muffler runs the longer it lasts. Mufflers on vehicles with catalytic converters run hotter and last longer than those on older vehicles without converters. Mufflers located ahead of the rear axle last longer than those located aft of the rear axle.

Mufflers rust from the inside out. Rust is caused by moisture in the exhaust. Moisture condenses in the muffler when the engine is shut off and the muffler starts to cool. Some mufflers have a small pin hole that allows condensation to seep out.

One aftermarket muffler manufacturer puts a small packet of a special moisture absorbing chemical inside some of their mufflers to fight internal corrosion.

A muffler that needs replacing is an opportunity to sell clamps, pipes, hangers and any special tools that might be needed to complete the job.

 

ALLDATA(R) Automotive Information System
This service facility is equipped with an automotive information system that provides this detailed data. The ALLDATA(R) system even lists high-tech specialty lubricants required for your particular car. Other information includes vehicle specific repair and diagnostic information and factory-issued Technical Service Bulletins. The bottom line is efficient, dependable and cost-effective service for you.