Car Safety – 10-point DIY Holiday Driving Reliability Checklist

These 10 DIY car safety tests will prevent a lot of breakdowns, not to mention roadside heartache. And you'll save $100 or so by doing them yourself

Remember that the time to do these car safety checks is, obviously, before you leave home. Because you might unearth a problem in the course of these car safety checks, give yourself time to have the car professionally repaired before your intended departure date.

Car Safety Test #1: Coolant level

Modern cars have a translucent plastic radiator overflow reservoir with ‘high’ and ‘low’ level marks. All you need to do for this car safety check is confirm visually that the (usually green) coolant level is between the two marks. If it’s low, wait for the car to cool down and top up with clean water to the mid-point between the two tide marks.

Car Safety Warning: Never remove the radiator cap when the engine is hot or warm. You could burn yourself as boiling water erupts from the radiator.

Car Safety Test #2: Radiator condition

Look closely at the front of the radiator: is it clogged with dead bugs (or grass if you’ve been four-wheel driving)? Radiators work using airflow – so if the front face is clogged, cooling capacity will be severely impaired. Your car could easily overheat in hot weather if airflow is obstructed. Carefully remove any debris – without damaging the fragile front cooling fins. Check also for evidence of water leakage – such as a salty stain. Look at the condition of the rubber hoses, too. Any that are bulging or cracked need replacing now - before they blow, halfway to your holiday destination, in the middle of the night.

Car Safety Test #3: Tyre pressure

Low tyre pressure is a car safety hazard, which causes many blowouts on the highway, and also increases the wear rate of the tyres while reducing their ability to grip the road. Car safety is significantly boosted with the right tyre pressures – found on the car’s ‘tyre placard’ inside the driver’s door. Inflate the tyres while they are still cold (a short drive to the service station is okay). If the placard has a ‘high-speed’ or ‘high load’ recommended pressure, use that. It is also quite safe to overinflate a tyre beyond the car maker’s recommendation, by as much as 10-20 per cent. Ride quality might suffer, but handling, grip and wear rate will probably improve.

Car Safety Warning: don’t forget to check the spare tyre pressure, because it is a deadest bummer of Biblical proportions to get a flat tyre, fit the spare, lower the car off the jack … and then discover the spare is also flat.

Car Safety Test #4: Tyre condition

Car safety in the wet demands adequate tread, so look at all four tyres’ tread faces. The minimum legal tread depth is 1.6mm, but at this level the tread’s ability to pump water away from under the tyre is already significantly impaired. Look for uneven tread wear, too (you might need a wheel alignment or other remedy – such as more regular tyre pressure checks). If tyre tread wear is uneven, consult an expert. Look also for bulges or other damage in the sidewall, which can indicate that tyre is terminal and could compromise your car safety while on the open road. Better to replace a defective tyre now than suffer a high-speed blowout, with potentially extreme consequences.

Car Safety Test #5: Engine oil level

Park the car on a level surface, pop the bonnet, and turn the engine off. Wait 30 seconds. Remove the engine oil dipstick and wipe with a clean rag. Re-insert the dipstick all the way in, wait a few seconds and withdraw. The engine oil level should be between the high and low marks on the dipstick.

Car Safety Warning: If you do only short trips normally, the engine oil often soaks up impurities (combustion byproducts basically) and doesn’t get hot enough to boil these away. The level can be artificially boosted by these impurities. For this reason you should always re-check your engine oil level at (say) the first fuel stop during a long trip. Your engine oil level might drop substantially in this initial highway driving period. It’s generally not a severe problem, but some people decide their car is consuming oil (that would be a problem). In fact, all that has happened is that these diluting impurities have been evaporated off. If this happens to you, top up the engine oil with the right grade (it's much cheaper generally to buy this before you depart, rather than at a roadside stop). Don't press on if the engine oil is low. Apart from its job as a vital protector of the engine's internal components, engine oil also plays an important supporting role in engine cooling. 

Car Safety Test #6: Other vital fluids

Get out the owner’s manual. (No, seriously: get out the owner’s manual. The what? The owner's manual.) You also need to check the brake fluid level, clutch fluid level (if a manual) or the auto trans fluid level (if an auto), plus the power steering fluid level and the windscreen washer fluid level. These are all easy enough to do – and an early once-over here could prevent a serious car safety mishap on the open road.

Car Safety Test #7: Lights

Wait for nightfall, or get an assistant. (At night you can do this easily on your own.) Confirm that the parkers, low beam, high beam, tail lights, brake lights (all three of them), reversing lights, indicators and four-way ‘hazard’ flashers are all working. Jump out and confirm the front and rear number plate illumination is also working.Dysfunctional lights (whether they're on the car itself of a trailer are a major car safety hazard.

Car Safety Test #8: Drive belts

Most modern cars have a serpentine drive belt at the front of the engine. Have a quick look at this (engine shut down, of course) for evidence of fraying, which indicates its imminent departure from service … and your imminent stranding at the roadside.

Car Safety Warning: a running engine is a serious car safety hazard. Particularly at risk are loose clothing, ties, long hair and fingers - all of which are easily and violently sucked into a running drive belt. Secure loose clothing, tie up your hair, remove ties and generally keep well away from a running engine.

Car Safety Test #9: Road test

Car Safety Test #9: Take a brief drive in the car and pretend you’re a doctor. Or, at least, a detective. See if the car tracks straight on a flat piece of road. If it pulls to one side you might have a wheel alignment problem. Check the rear-vision, and if there’s no traffic behind you, perform a series of three or four progressively harder brake applications, with the last one activating the anti-lock brakes. (Don’t worry: hard braking a few times won’t hurt the car.) See if the car continues to track straight. If not, and the car pulls to one side, you need to see a brake specialist. If all four stops feel nice and solid, as well as easy to control, the brake system is functional. Ensure that there’s no grinding or squealing noises (which could indicate worn-out brake pads). If your car has anti-lock brakes, the pedal will pulsate underfoot and there might be a juddering niose. That's normal.

Car Safety Warning: The worst time and place to discover you have a brake problem is during an emergency stop…

Car Safety Test #10: Windscreen wipers

Run the hose over the windscreen and test the wipers. If the wipers swipe the screen cleanly, with no juddering, you’re good to go. If not, replace the blades. Check that the washers are freely flowing as well.

Car Safety Warning: vision is already significantly impaired during rain. Don’t make driving in the wet even more dangerous on the highway by setting off with windscreen wiper blades that have given up doing their job. Wiper blades are cheap, and defective or worn ones are a major car safety hazard.

Gear up

It’s a great idea to pack a reflective hi-viz vest (in case you need to fix a flat tyre at the roadside) as well as a head torch (because breakdowns often happen in the dark, and being able to see AND use both hands is a night-time car-repair bonus). A small plastic tarp is a great addition to the boot (unless the notion of lying down in the mud fixing the car appeals). Some drinking water, sunscreen and a hat are a great addition to every boot (because you might have to wait some time in an otherwise inhospitable place for roadside assistance) and some spare engine oil, a can of WD40, some rags, hand cleaner, a Leatherman multi-tool and some spare fuses won’t hurt either. Carry a GPS navigator, because that will make it easy for you to tell roadside assistance operators where you are in unfamiliar territory. 

Finally, get roadside assistance organized before setting off. This is always cheaper than organizing it after you've broken down, and in fact it's some of the cheapest insurance you will ever arrange. (Remember that not all breakdowns are preventable.) If you do break down in a holiday period, be prepared to wait, because roadside assistance services are often overwhelmed during these times. Be patient.