If your goal is to keep your car in great shape, don't even consider doing any of these things.


1. Never Ignore Rusting

Car rust is every car owner’s worst nightmare! And if it isn’t, then it probably should be. Not only is it extremely unsightly, but it’s also potentially dangerous in large amounts and, the tricky thing about vehicle rust is that it’s almost always worse than it appears on the surface.

If you notice rust bubbling through your vehicle’s paint job, don’t ignore it, or worse still, try hide it under a bit of paint or a decal you bought at China Mall. Rather, do some careful poking and prodding of the area, and you’ll probably discover a section of metal beneath the paint at least two or three times larger than the visible rust bubbles. Spots like this need to be stripped back to clean metal, then filled and repainted as soon as possible. Small nicks in the paint that become rusty are likely just surface rust and aren’t as urgent, but still shouldn’t be ignored for long, lest they get worse.


2. Never Overfill the Tyres to “Get Better Fuel Consumption”

The internet is bursting with testimonials from people who claim they bettered their fuel consumption by inflating their tyres to, or even beyond, the maximum pressure listed on the sidewall. But here is what they neglect to tell you about: a rougher ride, premature tyre wear, longer stopping distances and hefty repair costs due to worn-out suspension components.

The recommended tyre pressure for your car is listed inside the driver’s door frame. The manufacturer takes into consideration the mass of the vehicle as well as the optimum handling when specifying the tyre pressure. With reference to the picture above, you will see two tyre pressure ratings, “Normal Load” and “Max Load”. Max Load would be when you are hauling something heavy, say the old Gypsey Regal to Tamboti, but you should remember to reduce the tyre pressure back down to “Normal Load’ pressure once you have removed the load.

Admittedly, the internet mechanics aren’t entirely wrong. Driving a normal load on over-inflated tyres does reduces rolling resistance, which can be slightly beneficial to your fuel economy. However, several negative effects outweigh this small benefit. Over-inflation increases stopping distances, causes the tyres to slip and hydroplane on wet roads, and reduces the life of the tyre. The harder tyres also absorb less impact vibration, so they transmit more road shock to your entire suspension system, causing a rougher ride. Worse yet, the additional tyre bounce wears out your car’s struts, strut mounts, shocks, springs, ball joints and control arms much faster.


3. Never Use the Wrong Coolant/Antifreeze

Most people know top up their coolant before we enter the height of summer or the depths of winter. However, there is more to it, than merely emptying a litre of anti-freeze/summer-coolant into your reservoir. Using the right coolant is critical to the life of your car’s engine and all cooling system components.

The recommended coolant for your car is listed in your owner’s manual. If you use the wrong coolant or mix different types of coolant, you can cause premature failure of your water pump, radiator, heater pipes and heater core.

That’s because corrosion inhibitors are designed to be compatible with the specific metals used in the engine and cooling system. Each inhibitor package also must be compatible with the types of plastic and rubber used in seals, gaskets and tubes used in your engine.

If you mix coolants, the corrosion inhibitors in one type can be incompatible with the additive package of coolant already in your car. The inhibitors in the added coolant can reduce the effectiveness or even cancel out the performance of the corrosion inhibitors of the old coolant. Worse yet, topping off with the wrong coolant can damage the plastic and rubber seals and gaskets used in late model engines. This sort of damage does not show immediately and won’t for several thousand kilometres.  When those parts fail, you probably won’t connect the dots and realize they failed because you used the wrong coolant.

Beware of the “universal” coolants stocked at supermarkets. All good spare shops will keep a range of the different colour coolants, and it is worth paying slightly more to get the correct coolant for your vehicle. It’s a small price to pay for peace of mind and increased vehicle lifespan.


4. Never Mix Up Brake Fluid and Power Steering Fluid

A one-pint bottle of power steering fluid looks very similar to a one-pint bottle of brake fluid, especially when they both sitting on a dusty shelf in your garage, with a fine layer of grime obscuring the label.  Perhaps that’s why so many DIYers mix them up (it happens more often than you think). If you add the wrong fluid to your power steering or brake system, the repair can easily run into the  thousands.

Power steering fluid swells the seals in a brake system, causing total brake failure. To fix the mistake, the workshop has to rebuild or replace the master cylinder, callipers, wheel cylinders and proportioning valve. In some instances, they may even have to replace expensive ABS components. Pouring brake fluid into your power steering reservoir is just as damaging because brake fluid isn’t a lubricant, so it causes pump and steering gear failure.

Always double check before you refill your brake or power steering fluid reservoirs.


5. Never Use a “Universal” Fluid in Your Power Steering or Transmission

Following on from the previous point, do not use a product which purports to be a “universal” power steering and transmission fluid for all car makes and models.

There is a reason that car manufacturers specify a very specific power-steering fluids, and the reason is not greed (as many people believe), but rather based on incompatible specifications.

As nice as “universal” fluids sound, there’s simply no way a single transmission or power steering fluid can meet the different (and mutually exclusive) viscosity and additive requirements for every transmission and power steering system in use today. In fact, European, Japanese and domestic car makers have differing transmission and power steering fluid requirements from model to model and even year to year.

The recommended fluid for your car’s transmission and power steering system is listed in your owner’s manual. It’s simply not worth the risk to use a non-approved fluid in expensive components like your transmission or power steering.


6. Never Disconnect a Battery Cable to Test the Alternator

Back in the good old days when fuel was 10c to the litre, you could disconnect a battery cable while the engine was running to test the alternator in your car. If the engine continued to run, that proved the alternator was working.

But it’s a test you should never try on a modern vehicle equipped with computers and electronics. The reason? Well, disconnecting a battery cable while the engine is running causes the alternator to spike a 25-to-125-volt surge within 40 milliseconds after cable removal. That voltage spike can’t damage anything in an old non-computerized car, but it can instantly fry the many computers and expensive electronics used on all late model cars. Repairing the damage can cost a small fortune.

If your car or truck was built after the early 1970s, chances are it has at least one computer. So, forget this old trick your grandfather told you about and test your car alternator with a volt meter. Or take your car to a fitment centre that offers a free charging system diagnostic test.


7. Never Drive When Your Oil Light is On

All cars have a “low oil pressure” warning light. If the light comes on while you’re driving, it can mean that your car is dangerously low or completely out of oil. It can also mean your car has a serious leak that’s causing a pressure drop, a clogged oil passage that’s causing oil starvation, or that the oil pump has failed or is failing.

Whatever the cause, when the light comes on, pull off the road immediately and shut off the engine. Then open the bonnet and check the oil level using the dipstick. If the dipstick shows you’re out of oil or dangerously low, you must add more oil before restarting. Driving a car when it’s dangerously low or completely out of oil will destroy your engine in just a few minutes, and that can easily mean a complete engine rebuild.

Don’t even contemplate driving to the nearest store to get more. It’s not worth the risk. Instead, call a friend or family member and ask them to bring the oil to your location. Or better yet always keep a litre of oil in the boot of your vehicle. (The recommended type and viscosity are listed in your owner’s manual). Add it to the filler port and check the dipstick to make sure it’s full. Do not overfill.

If the dipstick shows you’ve got oil, the problem is even more serious and must be checked out by a mechanic. There’s really nothing you can do while you’re on the side of the road. If the dipstick shows the engine is full, or you can’t reach a friend to drop off more oil, call a tow truck. If you can’t afford a tow, then you surely can’t afford a new engine.


8. Never Drive With Less Than a Quarter Tank of Fuel

The electric fuel pump is located inside the fuel tank on just about every fuel-injected car and truck. Vehicle manufacturers put it there on purpose, so it’s cooled and kept at a safe operating temperature by the fuel in the tank. But if you consistently drive with less than a quarter tank, the low fuel level can’t always provide sufficient cooling for the pump, and that can cause early fuel pump failure. Overheating isn’t the only issue, though.

Consistently driving with a low fuel level causes the pump to suck in debris from the bottom of the tank. That debris can clog the fuel filter, and those which make it through can wear out the pump impeller, causing a low fuel pressure situation. This warning doesn’t mean you have to rush to a gas station the instant you hit a quarter tank on the gauge. The fuel pump can easily handle occasional low fuel level operation. But if you consistently drive with less than a quarter tank, you increase your chances of early fuel pump failure and a big repair bill.


9. Never Use the Wrong Oil

Greater sophistication in modern vehicle designs means using the right engine oil is crucial. Car manufacturers have upped their game on engine design to meet higher mileage standards. Newer engines are built to more exacting tolerances and include high-tech mechanisms like variable valve timing (VVT) and turbochargers to squeeze more power and miles out of every litre of fuel.

VVT systems work by pulsing pressurized oil into hydraulic passages to advance or retard the camshaft. The pulse timing and associated camshaft movement is based on the oil type and viscosity listed in your owner’s manual. It all works great if you use the right oil, and it gets severely messed up if you use the wrong oil. Using the wrong viscosity oil can actually set a trouble code and light the “check engine” light on your dash.

The right oil is just as critical for proper turbocharger operation. A modern turbocharger can spin at rates as high as 240,000 RPM, which means the bearings must be constantly lubricated and cooled by the oil. If you substitute a different oil type or viscosity, you can change the flow rate, causing bearing overheating and early turbo failure. 

So, ignore the advice from your buddies or online “oil experts” and stick with the car manufacturer’s oil recommendation. They designed the engine and they’re in the best position to know what fluids it needs. 


10. Never Use Dishwashing Detergent to Wash Your Car

Dishwashing detergent is designed to aggressively attack and break down dried on food, oil and grease. That’s great for dishes — not so great for car paint.

Car paint, clear coat and car wax contain oils and resins that maintain the paint’s integrity and filter out harmful UV rays. When you wash your car with dishwashing detergent, you strip off the wax and pull some of those critical oils out of the paint and paint sealants, leaving it bare and exposed to the elements.

If you immediately wax your car with a high-quality wax, you can restore some of the UV protection. If you don’t wax your car after washing with dishwashing detergent, you lose important sun protection. If you regularly wash your car with dishwashing detergent, you’ll degrade the paint and clear coat enough over its life to cause premature fading and even early paint failure

Dedicated car shampoo, on the other hand, is designed to remove dirt and grease without removing the surface wax and oils from the paint. It’s also biodegradable, so the wash water runoff is safer for the environment. Browse our extensive range of Shield, Holts and Waxco car soaps and shampoos. They are relatively cheap and better for your car’s finish.