I N THE GARAGE:

Assess your car’s brakes and running gear.

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Disassembly and tyre-wear check Place chocks on both sides of both wheels on the side of the car opposite to where you intend to work. On the first wheel, remove any accessories such as hubcaps and ‘crack’ the wheel nuts loose.

Jack up the vehicle until the wheel is free to turn. (Place a rubber mat under the jack if the floor is smooth). Now, position the safety stand under a sturdy part of the underside of the vehicle. Lower the jack until there is enough of the vehicle mass on the safety stand to keep it firmly in place.

Now spin the wheel and check it for any wobble or damage. Check the tyre treads and sidewalls. Listen for rumbling wheel bearings. Grip the tyre at the top and bottom, and apply alternating force with each hand to check for wheel-bearing wear. If they’re worn, there will be a distinct amount of play as you do this. If this is the case, make a note to take your vehicle in to have replacement bearings fitted as soon as possible.

Now remove the wheel nuts and take off the wheel. Examine the inner walls of the tyre for damage that may have been previously hidden. Check for evidence of ‘thrown’ balance-weights – they will appear as clean patches where the weights once were.

Drum brakes Older vehicles may have drum brakes at both the front and back. The drum may come free once the wheel is off, or you may have to first remove the wheel bearing retainer split- pin and castellated nut, or there may be a couple of countersunk retainer screws, usually with Phillips-heads, holding the drum in place. (These may be rusted tight. If so, use a 10 mm- diameter punch and give the head of the screw a couple of sharp taps to jolt the rust loose, or use a hammer-screwdriver). Remove them and ease the drum away from its seat. The brake shoes may offer some resistance here. Be sure not to ‘cock’ the drum against the shoes – rather rock it off with small movements either side.

Now brush and vacuum off all the dust from the brake shoes and slave cylinders. It’s always tempting to use an air-hose for this but don’t: Brake dust is toxic.

Check that you still have at least 2.5- to 3 mm of brake lining on the shoes. If not, either remove them (this task is beyond the scope of this article), and take them to a reputable brake service centre for replacement, or book your vehicle in soonest.

Check the slave cylinders for leaking brake fluid. This will be evidenced by a thick layer of wet black dirt caked on the cylinder and brake shoes. If the leak is severe, the brake shoes will have become glazed and will have to be replaced. (Servicing the slave cylinders is also beyond the scope of this article, and must be done by the experts).

Replace the brake drum.

Disc brakes With disc brakes, we check the actual disc for wear and grooves. Brake discs are all 12 mm thick, or more. If yours are less than 12 mm thick and are grooved, possibly with a ridge around the perimeter, take your vehicle in for professional replacement.

The actual brake pads are held inside the calipers, which are the big assemblies through which the discs rotate. Once cleaned, you should be able to look in through the edge and determine how thick the pads are. Generally, pads of 3 mm or less must be replaced. Again, if this is the case, we advise that you take your vehicle to o your competent service centre. cent e Bleeding your b brakes akes This work is safety critical, so unless you’re 100 per cent confident in your ability to carry out the necessary tasks, rather hand it over to your trusted service agent.

Brake fluid is hygroscopic. This means that it will absorb moisture over time and when this happens, it may vaporise due to the heat generated during severe and prolonged braking. This ‘vapour lock’ could cause your brakes to fade about halfway down a mountain pass, especially problematic if you’re towing an unbraked trailer.

It’s for this reason that I recommend you change your brake fluid every 24 months. This job needs two people: One to sit in the car and push the

brake pedal and one to drain the fluid – time to grab your husband, wife, or one of your children as an assistant.

Start at the wheel, which is still jacked up, with both the wheel and tyre removed. You’ll find a bleed nipple under a rubber cap, behind the backplate on drum brakes, and on the caliper for disc brakes.

Remove the rubber cap and push your clear plastic hose over the nipple. Lead the free end into the jam jar. Find a spanner to suit the hexagon at the base of the bleed nipple.

Check that the brake-fluid reservoir, (under the bonnet and to one side of the engine), is full. To perform the bleed cycle, perform this sequence exactly: • Have your assistant put moderate pressure on the brake pedal, but tell them not to lift their foot until you say so. • Loosen the bleed nipple until brake fluid flows into your clear plastic pipe. • As soon as the flow stops, (the brake pedal has reached the floor), nip the bleed nipple closed. • Tell your assistant to lift their foot.

Check the fluid level in the reservoir. Try to get this level as low as possible by repeating the bleed cycle, but, very importantly, do not expose the drain holes at the bottom of the reservoir, as this will introduce air into the brake pipes leading to your wheels and make your brakes spongy.

Now, top up the reservoir with new, clean brake fluid and continue with the bleed cycle, topping up as necessary, until you can see the new, clean fluid flowing through your plastic pipe.

Tighten the bleed nipple securely, replace the rubber cap, and repeat at your other wheels. And there you have it. Wasn’t too difficult, was it? And you don’t have to do it again for at least two years. Next, the suspension. Shock absorbers While you have your head under the mudguard, check your shock absorbers for oil leaks, check that the mounting bolts are tight and that the mounting rubbers are sound. Should there be any leaks or worn rubbers, have the shocks replaced by an expert.

Your final shock-absorber test will be after you have the vehicle off the stand and on all four wheels again: Push your full body mass firmly down at each corner of your car and release quickly. The car should return to its normal height with no evidence of bounce. If it bounces on the springs, then your shock absorbers are not functioning as they should and you should have them replaced.

Springs If you have leaf springs, check for broken leaves and that the clips that keep the stack of leaves aligned are still intact. Insert a tyre iron or tommybar into both the front and rear mounting points and exert sufficient force to verify whether all of the mounting bushes are still intact. Check that the bolts that actually connect the springs to the chassis all have either nyloc nuts or locknuts, and that they are all tight. Finally, check that the U-bolts that connect the axle to the leaf springs are all sound and that the nuts are all nice and tight.

With coil springs, you’ll easily see a broken coil, which would’ve resulted in a serious sag in any case. Torsion bars and swing-arms Layouts can be very diverse, so I can’t describe them all here. Just examine all the components carefully, looking for damage and loose or missing nuts and bolts. A small tommy-bar or tyre iron on a hinged connection is a good way to tell if mounting bushes are worn.

If any damaged parts are discovered, book your vehicle in with your service agent as soon as possible.

Finishing touches Once you’ve completed the tasks on all four corners of your car, replace the last wheel, nip up the wheel nuts and lower the car to the ground.

Now, vitally, tighten the wheel nuts, preferably with a torque wrench to the manufacturer’s specification, or else bliksems-vas (the technical term) if you’re just using your wheel spanner.

You’ve just done an in- depth check of your vehicle and saved yourself at least a thousand rand. Time for a beer.