VEHICLE FREQUENTLY ASKED QUESTIONS (FAQs)

We value our customers and all their questions. This is Isuzu's Frequently Asked Questions (FAQs) sections answered by Isuzu for our customers.

In the course of our operations, we have been privileged to read, hear and discuss feedback from our valued customers. It's truly a very enriching experience listening to their concerns, suggestions and comments. In particular, we enjoyed answering our customers' questions about our products.

To service our customers better, we have decided to put together the questions they most frequently ask, as well as their corresponding answers, so that our customers could read them and go back at their own leisure.

This is our way of saying THANK YOU for giving us a chance to be your Responsible Partner!

Please pick a question from the drop-down box:

What does the label on the motor oil container indicate? How do I check my engine oil level? How does engine oil work? How will I know the right tire specification for my Isuzu vehicle? What is the proper way to check tire pressure? Why is tire rotation essential for vehicle performance? How do I interpret tire wear? How often should I have my wheels aligned? What causes wheels to be misaligned? How do brakes work? Why are my brakes sometimes weak? How can I maintain the good paint condition of my Isuzu? What causes premature rust formation? What tips can I follow to prevent premature rust formation? What is "Direct Injection Diesel"? What is a turbocharger? What is an intercooler? How do I take care of my turbocharged vehicle?

On every bottle of motor oil there is a seal that contains the following information:

        - The American Petroleum Industry (API) service rating
        - The Society of Automotive Engieners (SAE) viscosity grade
        - "Energy Conserving" indicator

The service rating is a 2-letter rating that tells you the type of engine the oil is meant for (gasoline or diesel) and its quality level. The first letter indicates the vehicle fuel type that the oil is designed for. Ratings that begin with an "S", which stands for ‘spark’, are intended for gasoline engines. Ratings that begin with a "C", which stands for ‘compression, are for four-stroke and two-stroke diesel engines. The second letter designates the quality level of the motor oil. The higher the letter, the more advanced the oil and the more protection it offers your engine (i.e., a “B” rating offers more engine protection than a “A” rating).

The viscosity grade (for example, 10W-30) tells you the oil's thickness or resistance to flow. Thin oil has a lower number and flows more easily, while thick oil has a higher number and is more resistant to flow.

There are two types of motor oils, single grade and multi-grade. A single grade oil with a 10W rating indicates that it will perform well in cold weather, the “W”, for winter, signifying that the oil meets viscosity requirements for low temperatures (below 30°F).

Multi-grade oils, such as a 10W-30, are designed to have the viscosity of a single grade 10W oil at cold temperatures combined with the viscosity of single grade 30 oil at engine operating temperatures.

Oils displaying the ENERGY CONSERVING label are formulated with friction modifiers to improve fuel economy in an industry standard test.

How do I check my engine oil level?

The crankcase oil level should be checked regularly. Our driver and owner’s manual suggests it should be done before driving your vehicle. It should be performed even with a vehicle that consumes very little oil, since a sudden leak in a gasket, oil line, filter, or seal could result in rapid oil loss, which could in turn result in engine damage.

REMINDER! The best time to check your oil level is before the operation of the vehicle, with the unit parked on level ground. If the engine has been running, stop the engine and wait for 5 minutes to allow the oil to drain back into the oil pan.

Pull out the dipstick and wipe it clean before reinserting to check the oil level to ensure that you get the right reading. The oil level should be kept between the "add" and "full" marks on the dipstick.

Overfilling can cause the crankshaft to excessively churn the oil, thus producing foam. This can impair the oil's lubricating characteristics and also lead to oil loss. On the other hand, if the oil level is too low, the oil volume may not be sufficient to handle cooling requirements and contaminants, which could result in buildup of deposits. A low volume of oil can also cause the oil to overheat, increasing oil deterioration rate. In extreme cases, the feed of oil into the suction side of the oil pump may be interrupted, resulting in oil starvation to the bearings and other moving parts of the engine.

Checking the oil level regularly is also an opportunity to check for any contamination in the engine oil.

How does engine oil work?

In an internal combustion engine, the engine oil is contained in the sump, or crankcase. The oil pump draws the oil through a screen, which strains out foreign particles, then forces it through a filter, which removes smaller contaminants. The filtered oil then circulates through passages drilled in the engine block to bearings, the valve mechanism, the pistons, the cylinder walls and other engine components that need lubrication, before returning to the sump. A bypass valve ensures that oil will reach engine parts if the filter becomes clogged. In some engines, lubrication may be accomplished in part by splashing caused by rotation of the crankshaft in the oil.

One of the major components of engine oil performance is protection against wear deposits, and oil deterioration. By incorporating additives, for example an anti-wear additive, wear between heavily loaded engine parts are greatly reduced. Detergents and dispersants help prevent buildup of contaminants, sludge, soot and varnish causing the oil to assume a black color even after a recent oil change. Oxidation inhibitors help prevent lubricant breakdown at high operating temperatures, which increase oil viscosity and impede oil flow to critical engine parts.

In diesel engines particularly, the combustion process results in the formation of large quantities of soot (carbon particles), which contaminate the oil and diminishes its anti-wear properties. For this reason, it is essential to drain and change the oil before it loses much of its ability to prevent contaminants from accumulating on critical engine parts. Extending the oil change interval beyond that recommended by the manufacturer could void the warranty.

How will I know the right tire specification for my Isuzu vehicle?

It is important to note that the recommended inflation pressures may differ for the front and rear tires. Tire inflation pressure should be more or less equal side-to-side.

WARNING! Never exceed the maximum inflation pressure specified on the sidewall of the Tire. This number is the maximum pressure tire is designed to safely handle.

What is the proper way to check tire pressure?

It is recommended tha
t tire pressure be taken from “cold tires”, meaning the tire condition before the vehicle is moved or driven. Driving heats up the tires (“hot tires”) and causes the air inside to expand. If you check tire pressure from “hot tires”, the reading will be at least several pounds higher than normal.

Here is how to check your tire pressure:

1. Remove tiny black valve cap on the valve that protrudes from the tire.
2. Press the round part of the tire gauge firmly onto the valve.
3. Read the gauge like a thermometer. The highest number you see closest to the stem of the gauge is the PSI or Kg / cm2. That number should match the recommended air pressure for your tire.
4. If the gauge reading is higher than it should be, use your finger, or the notch on the opposite side of most tire gauges, to release a bit of air by pressing it on the pin inside the tire valve.
5. If the gauge reading is lower than it should be, use the pump to add more air.
6. Check your tire pressure again, and see if you get the right PSI.

WARNING! A tire can lose up to half of its air pressure and not appear to be flat.

REMINDER! Check inflation pressure (including the spare) at least once a month and before every long trip.

Because your vehicle’s tires perform different jobs, they often wear differently. Tires on the front and the rear of the vehicles operate at different loads and perform different steering and braking functions. To get the longest wear from your tires, and help them wear at the same rate, it is necessary to switch their positions every once in a while. You should consider rotating your tires, front and back, every 9600 kilometers (6000 miles).

Here are some simple diagrams (A = including the spare tire, B = only the four tires) to help you with your tire rotation:

When the front tire size and the rear tire size are different, interchange front wheels and rotate the rear wheels as shown in the figure:

 

When the front and rear tires are the same size, rotate the wheels as shown in the figure:

 

For radial tires, interchange the front and the rear wheels on the same side as shown in the figure:

 

If one-sided tire wear appear on radial tires, rotate the wheels as shown in the figure:

 

WARNING! Front and rear tires on a vehicle use different pressures. It is advised that after rotation, adjust individual tire air pressures.

The manner by which your tires show wear is a good indicator of other parts of suspension. Ball Joints, Tie Rods, Bushings, Struts, Shocks, Coil Springs, Leaf Springs, U Joints and Drive Axles, -all these suspension parts play a vital role in the safety and handling of your vehicle.

Abnormal wear patterns are often caused by the need for simple tire maintenance, or for front-end alignment

 

If a tire looks like this, it may be under inflated. The worst enemy a tire could have is probably too little inflation pressure. Under inflation reduces tread life through increased tread wear on the outside edges (or shoulders) of the tire. It also generates excessive heat, reducing tire durability. Finally, it decreases fuel economy through increased rolling resistance (a soft tire makes your vehicle work harder).

 

When a tire is over inflated, the center of the tread bears most of the load and wears out faster than the outside edges. Uneven wear reduces the useful life of a tire, and the size of the contact patch is reduced. This increases the likelihood of traction loss in imperfect road conditions. An over inflated tire tends to wear unevenly, often leading to “scalloped” tread wear

 

Cupping is most common on front tires, though rear tires can cup as well. It may be a sign that wheels are out of balance or that suspension or steering system parts are worn out. Cupping is a condition caused by the tire bouncing as it rolls. Small areas of heavy wear are created. Worn shocks are often the cause of cupping, but loose suspension parts or tire imbalance are also possible causes.

 

Do the edges of the tread take on a Sawtooth or feathered appearance? This is caused by erratic scrubbing against the road, as only one side hits the pavement. This is due to misalignment as could be corrected by toe-in (for outside wear) or toe-out (for inside wear)

IMPORTANT! Check you tires before each trip!

Isuzu recommends alignment every 10,000 kilometers or every six (6) months. This interval on wheel alignment schedule at our Isuzu Authorized Service Center plus necessary adjustments can add thousands of kilometers to your tires over the years. That's money in your pocket in tires not bought and extra fuel not burnt. Of course, when you change tires, that's an excellent time to have your wheels aligned.

For most standard Asian Utility Vehicles and Passenger Cars, a wheel alignment will cost around P 1,000 – 1,500. There is usually an extra charge for vans, 4x4's or 4-wheel steer cars, and it takes about an hour to do.

REMINDER! Take care of your tires! At any sign of unusual wear, bring your Isuzu to your dealer without delay.

Even without abuse, front wheel alignment will change under normal, everyday driving conditions. The change may be so gradual that it is not noticed at first. The first sign of something wrong usually shows up on the front tires, which develop peculiar wear patterns that will severely shorten the life of the tire.

Hitting potholes, rubbing curbs and bumping concrete parking stops knock things in your steering and suspension. This eventually, leads to misalignment. Your car could pull one way or the other or the steering wheel might resist you when you turn or hold to maintain a straight course. When these symptoms manifest, bring your Isuzu to your dealer for an alignment check.

 

A wheel alignment job should always start and end with a test drive.

The front end and steering linkage should be checked for wear before performing an alignment.

The tires should all be in good shape with even wear patterns.

NOTE: Pulling problems are not always related to wheel alignment. Tires, brakes and power steering could also be the culprit. It is best to consult your Isuzu service representative to determine the root of the pulling.

Brakes are actually energy conversion devices, which convert the vehicle’s momentum into heat energy. This heat energy produces a force ten times more powerful than the force that keeps a vehicle in motion.

The basic process of converting a vehicle's momentum into heat energy has not changed much since the days of the horse and buggy. To stop a horse-drawn carriage, the driver would pull on a lever, one end of which comes in contact and rubs on the wheel, thus stopping the carriage.

 

For modern vehicles, when you step on the brakes, the mechanical pressure caused by your foot is converted into hydraulic pressure by the master cylinder, which contains the brake fluid. This pressure is transmitted to wheel cylinders placed in each wheel through steel brake lines and flexible brake hoses. The wheel cylinders then push on the brake shoes and brake pads to come in contact with the wheel’s drum and rotor, in the same way that a carriage’s lever would rub on the wheel, thus causing the drag which stops the vehicle.

Brake Fade is a temporary condition caused by high temperatures generated by repeated hard braking.

Repeated hard braking causes the brake linings (pads and shoes) that rub on the drums and rotors to create friction, heating up the brake fluid. The increased pressure and heat causes the brake linings to “glaze” or harden. Also, heating up the brake fluid too much can produce vapor on the brake system. When this happens, the friction provided by the lining decreases and consequently, the braking efficiency also decreases.

Water adversely affects braking efficiency; it would require increased pressure on the brake pedal to achieve the usual braking effect.

The heat generated when braking causes the water to boil and create gases, which prevent full contact between the linings and the drums and rotors.

After driving in heavy rain or across a shallow river or flooded area, it is recommended to step on the brakes repeatedly to test its efficiency. If you feel that the braking efficiency has deteriorated considerably, stepping on the brakes several times serves to evacuate water that may have penetrated the braking surface, thus helping restore brake efficiency.

WARNING! Depressing the brake pedal repeatedly may cause the brake warning light to come on when the engine is running at idling speed or at low speed. When you’re done, one hard brake application should extinguish the brake warning light.

Loose hydraulic connections, ruptured or damaged hoses or lines (causing leakage), worn or damaged master cylinder

When there is something wrong with the brake system, the brake system warning light will remain on even after the engine has been turned on and with the parking brake released, or when it comes on during operation of the vehicle.

When the brake warning system does come on during operation of the vehicle, check to see if the parking brake has been fully released and check the brake fluid level. If the parking brake has been fully released, pull over to the side of the road and stop carefully. Remember that stopping distances may be longer, you may have to push harder on the pedal and the pedal may go down farther than normal, or what is termed as a “sinking pedal”. Immediately contact an authorized Isuzu dealer nearest you and have your vehicle towed.

How do I maintain the good paint quality of my Isuzu vehicle?

Isuzu uses only the highest quality paint that maintains the integrity and value of your vehicles original factory finish using the advanced Electrodeposition coating or ED. In ED, a special method is taken in forming the paint film, by depositing a uniform and water-soluble paint film. A tank is filled with ED paint diluted with relatively low concentration of water and is passing through an electric current. One of the advantages of ED coating is the automated consistency system, which results in an excellent finish.

One of the major causes of paint deterioration is oxidation. The paint of a brand new vehicle is relatively oxidation free, and if you maintain your vehicle’s paint with regular washing and protection, oxidation will be minimized.

When cleaning your Isuzu, always use wet cloth for wiping, after rinsing the paint surface with water. Avoid using detergents as it can dull your car’s finish faster (most automobile manufacturers recommend using only pure water to wash your car, because even the mildest soaps can remove the natural oils from your unit’s paint, causing oxidation). Remember not to wipe dust off your car with a dry cloth or duster, as this will cause nicks and scratches.

Regular washing is important, since your vehicle attracts contaminants (i.e., road debris, birds dropping or tree sap). These should be washed off immediately; they contain acid and can ruin paint film. Polishing is also necessary to remove minor blemishes, and keep a perfectly smooth paint finish. It is also advisable to have your vehicle waxed at least once a year. This will keep UV rays from fading the paint.

By maintaining your vehicle’s paint in good condition, you can be assured that Isuzu’s best quality paint can last up to ten years.

WARNING! Do not wash, polish or wax your car in the heat of the sun, it could streak or stain the paint surface. Avoid parking your vehicle under direct sunlight for an extended period of time, as this will cause the paint to blister.

When iron or steel reacts with oxygen, it forms iron oxide or rust, which often causes the iron to puff up and flake easily thus causing erosion of the iron or steel. This phenomenon, called “pitting”, occurs because iron oxide or rust requires more physical space than the original iron or steel.

Some things cause steel or iron to rust faster than others do:

Rust occurs much more rapidly in moist conditions. As oxygen in the water reacts with iron, pitting occurs and rust formation follows.

Salt water and hard water (water from deep well) will cause rust faster than water because both are better electrical conductors. Living in “rust belt” areas where the vehicle is exposed to the ocean or salty air and commonly flooded areas, hastens rust formation.

Although rusting occurs much more rapidly in moist conditions as compared to a dry environment, the degree of exposure to direct sunlight also speeds up rust formation.

Humidity (relative wetness or moisture content of the air) can also speed up rust formation. When unavoidable, it is recommended to cover your vehicle using a breathable material. However, avoid a cover that goes all the way to the floor or one that traps moisture, as this will encourage condensation on the vehicle’s surface thus speeding up rust formation.

Dust is a very good magnet for moisture. Keeping dust off your vehicle by giving it a good rub down after traveling in a dusty area or use of a cover when the vehicle is parked are effective in keeping off dust and discouraging rust formation.

Rain, tree sap, bird droppings, dead insects and air pollution damage your vehicle’s finish. The finish, which is your vehicle’s first line of defense, consists of a thin layer of paint with a much thicker layer of glossy clear coat applied on top of the paint. Once you impair the finish of the car, you invite more destructive types of corrosion to take place.

1. Wash your vehicle regularly.
2. Park your car in the shade. When washing, let it cool off before you start. It is better if you can park on a slight incline as the water will run off more easily, and the car will dry more quickly.
3. Wash and dry your car with clean, soft towels, or car washing mitts. It is recommended to use all-cotton towels or synthetic chamois as most towels contain polymer fibers that scratch a car’s finish.
4. Use a good liquid detergent specifically designed for vehicles. If you want your wax to last longer, you may consider products based on detergent instead of soap. Soap manufactured from animal byproducts can damage your paint. Avoid detergents in powder form as the undissolved granules can scratch the paint surface.
5. Use a water hose to wet the car thoroughly from top to bottom. It is preferable to use a pistol grip hose nozzle set to create a medium-strong stream that will drive off bird droppings and other hardened deposits. Avoid using a high-pressure spray. They can damage a car by driving road grime into the finish, rather than washing it off.
6. Aim the hose up under the car and into the wheel wells to wash off road salt and dirt from those areas.
7. If there's still some bug splats, tree sap, or other material on the surface, use a pre-cleaning solution and remove it with a clean mitt or towel. The answer can be as simple as adding a spot of full-strength car detergent to a mitt or towel or pouring seltzer water on the stubborn bird droppings. Let it bubble up, then wipe clean. Bird droppings should be removed as soon as you spot them. The highly acidic droppings are very damaging to the car’s paint. Don't scrub the area and risk scratches. Birds use gravel to digest their food hence grit is one of the major components of their droppings. When possible wash area thoroughly after the droppings have been wiped clean with seltzer water and apply a coat of wax to remove all traces of acid.
8. Since there's more dirt on a car's sides and panels than on the top, hood and trunk, it is advisable to work from top to bottom. Switch to fresh mitts and towels when you get to these dirtier areas--again to keep scratches to a minimum.
9. Wash each area thoroughly by flooding it with a low-pressure flow. Don’t wash a section and then leave it to wash another. The dirty wash solution can dry on the surface, and then you're back where you started!
10. Gently blot up any remaining water until all the surfaces are dry. Opening the doors, trunk and hood will allow you to wipe up any water that trickled in. Finish by cleaning up the doorjambs with a damp towel--this will prevent water from dripping inside the car.
11. Waxing your car a few times a year adds an additional protective coating, helps maintain the resale value, and just might extend the car's life. Be sure to wax when the finish looks dull or when water doesn't "bead" on the surface. Otherwise, apply wax at least once per year. Always wax your car in the shade, or out of direct sunlight, as bright sun is bad for the raw wax. Always wash and dry your car well before you wax it so you don't grind anything into the surface.

 

The Indirect-injection system is currently limited to use in passenger cars and light-duty trucks. The most popular design has a spherical swirl chamber in the cylinder head. Air is forced into the chamber by the piston and begins swirling rapidly, which promotes a good mix when the fuel is injected. A preliminary combustion of the mixture takes place and heat rises, forcing the remaining unburned fuel into the chamber at high velocity, where it mixes well with the air and undergoes complete combustion.

 

Direct-injection system introduces fuel directly into the combustion chamber. Direct injection promotes good fuel economy, but the air’s swirling motion is not strong enough to promote an ideal mix with the fuel. This weakness is overcome, however, with specially designed chambers and air-intake ports, and high-pressure fuel injection.

Direct injection diesels are gaining increasing popularity. They are now used in nearly all trucks with payloads of four tons or more and a significant percent of passenger cars in Europe. The most popular direct-injection system produces a strong swirl of air in the combustion chamber to help mix it with the fuel, which is then injected under high pressure from four to five nozzle holes.

No, we are not the only one using this technology. Other car manufacturers use direct injection technology too.

A turbocharger (also called a forced induction system) gets its power from the exhaust stream. The pressure from the hot exhaust gases causes the turbine to spin. Since the turbine is mounted on the same shaft as the compressor, the compressor is forced to spin at the same time, drawing more air into the cylinders than is normal, or in vehicles without a turbocharger. More air means that more fuel can be stuffed in too; therefore you get more power from each air-fuel mixture explosion. A turbo-charged engine produces more power than the same engine without it.

In theory, a turbocharger is efficient because it is using the "wasted" energy in the exhaust stream for its power source.

WARNING! A turbocharger causes some amount of back pressure in the exhaust system and it also tends to provide less boost unless the engine is running at higher RPMs. The turbine in the turbocharger spins at speeds up to 180,000 rotations per minute (RPM) -- that's about 30 times faster than most vehicle engines can go.

As the turbocharger compresses more air into the cylinders, the compressed air heats up, causing the air to expand. However, to increase the power of the engine, the goal is to get more air molecules in, not necessarily more air pressure.

This is where an intercooler or charged air cooler does its work. It is an additional component to the turbocharger that looks something like a radiator, through which the compressed air passes to cool it off before it enters the cylinder. The intake air passes through sealed passageways inside the cooler, while cooler air from outside is blown across fins by the engine-cooling fan.

The intercooler further increases the power of the engine by cooling the pressurized air coming out of the compressor before it goes into the engine. This means that if the turbocharger is operating at 7 PSI boost, the intercooled system will put in 7 PSI of cooler air, which is denser and contains more air molecules than warmer air.

1. Change the oil at least every 5,000 kms, or more frequently with severe usage. Our New Vehicle Warranty Policy and Maintenance Booklet defines severe usage as any of the following:

              - Driving in dusty area or in area where the vehicle is likely to be exposed to salt or brine.
              - Driving on rough roads, submerged roads, or hilly areas.
              - Engine idling for a longtime or short distance travel.
              - Frequent and sudden application of brakes.
              - Operation under excessive load such as towing of a trailer or use as a taxi or rent-a-car.
              - More than 50% of operating time in heavy traffic; in hot temperatures of 32 degree Celsius or higher.
              - More than 50% of operating time at speeds of 100 km/h; in hot temperatures of 32 degrees Celcius or higher.

2. Do not use cleaning additives for it may loosen particles in any used engine.
3. Always let the engine warm up for about 30-60 secs before driving. Extend warm-up time, as the weather gets colder.
   WARNING! Cold, thick oil does not flow as freely as warm oil!
4. Do not rev engine during warm up time, the turbo may not yet have received a full supply of oil.
5. Always let the engine idle for 3 -5 minutes before shut down, otherwise the turbo will continue to spin without oil lubrication and pressure. The faster you have driven, the longer you should let it idle down.
   WARNING! Your turbo is free spinning at high RPMs. When the engine is shut off the oil supply is also shut off, which may result in bearing damage almost immediately.
6. Immediately after an oil change, the filter is dry or is without lubrication. Always prime the filter by applying a thin coat of oil then crank over engine without starting by placing the ignition or starter switch in the “ON” position until oil pressure is observed. The oil pressure indicator light should light up when the lubricating system is operating normally before the engine is started.

WARNING! If the light comes on while driving, it indicates that the oil pressure is dangerously low. Stop the engine and check the oil level in the engine crankcase with the use of a dipstick. If the oil level is normal, have your lubricating system checked by your nearest Isuzu dealer.