UNDER-CAR CHECKS
Power steering fluid leaks tend to come from either the top pinion, or beneath the gaiters, caused by failed internal seals – all of which dictates that the steering rack has to be removed and dismantled. However, grease can emerge from end gaiters. Like driveshaft gaiters, torn rubber is an MOT failure point and will permit moisture and grit to permeate the joint, wearing it out prematurely. While light perishing is acceptable, check suspension rubber bushes for deep cracks, or even disintegration. A typical MOT inspection will check for excessive wear (see Pass the MOT Test, CM, November 2017), but a close look at servicing time can preempt any potential problems. Inspect all pipes for excessive rusting or chafing and make sure they are all mounted securely to the underbody. Ensure that all plastic clips are in good condition and are not coming away from the floorpan. Check the integrity of any electrical wiring as well.
On rear-wheel drive or four-wheel drive cars, check and service the propshaft. Ensure that any support bearings are in good order and that the universal and sliding joints neither exhibit play, nor require greasing. If necessary, a grease gun can be connected to a nipple to inject lubricant into the joint.
Some 4x4 vehicles, notably those fitted with Haldex coupling systems or similar, require periodic oil and filter changes. Again, consult your vehicle handbook and maintenance information for advice. While this task may be beyond the capabilities of novices, more experienced Diyers should have no difficulty.
Alternatively, on rear-wheel drive, or 4x4 vehicles, check the differential oil level within the rear axle casing in the same way as checking the gearbox fluid level. Note that the oil specification might not be the same as that dictated for a manual gearbox.
As your inspection involves removing the wheels, check the tyre tread for any uneven wear and both sides of the sidewall for cuts and bulges. Using an alloy wheel cleaner, clean both the inside and outside surfaces of aluminium alloy rims, prior to coating their contact points with copper grease. With the wheels off, inspect the suspension strut (if fitted) for broken springs and leaks emanating from the shock absorber. If visible, especially on the rear, check that the bump stops (which may be mounted to either the suspension or, bodywork) are intact and in good order – the one pictured is broken. After examining any other relevant parts that are accessible with the wheels removed, including cables, gaiters and suspension balljoint gaiters (shown here), clear any accumulated mud from under the wheelarch, prior to refitting the wheels and tightening the nuts or bolts to the specified torque. With each wheel in the air, rock it lightly to check for play. While movement or light ‘clonks’ might be caused by a worn suspension part, most wheel bearings should exhibit no play whatsoever, unless taper bearings are fitted, in which case the end-float might require adjustment. Consult your workshop manual.
When refitting the undertray, grease any bolt threads so that they will be easy to remove at the next service. Do not be tempted to drive with any missing or broken clips, because the tray can become detached surprisingly easily. You may have to create your own innovative means of repairing broken sections (see inset pic).
When refitting engine covers (see Step 2), check that the mountings are in good order – on diesels especially, where they are important in reducing vibration being transferred into the cabin. Replacements tend to be inexpensive and having them in good order reduces the risk of the panel working loose, when the car is driven. After washing the bodywork, verify that all drain holes in the doors, sills, sunroof, etc, are clear. Check for any rust spots and apply a rust converter, followed by primer and paint, to any suspect areas. Lubricate any locks and latches – an operation that tends to be overlooked. Pay particular attention to door check straps, which tend to suffer the most wear. If the strap is secured to the door pillar by a bolt, ensure that it is tight. Additionally, battery terminals should be greased with petroleum jelly. Windscreen wipers should be in good order – split or perished rubbers must be replaced. It is also good practice to renew the wiper blades every 12-18 months, not only to maintain optimum vision but also to reduce the chance of minor scratches on the swept area of the windscreen. After polishing and waxing the bodywork, reset the service indictor. This can be done by manipulating the buttons on your instrument cluster (see your workshop manual), or by using diagnostic equipment (as detailed below). Do not forget to make an entry in the service history showing that the work has been completed. Replace the air-conditioning/climate control pollen/cabin filter on cars where one is fitted. Consider paying extra for a new filter that has been carbon activated, which will remove odours and certain pollutants in addition to capturing dust, pollen and other contaminants. The evaporator within the airconditioning system (located deep within the dashboard) tends to attract mould growth. Consider using an aerosol ‘bomb’ that kills the spores, thus preventing them from entering the cabin via the vents and causing illness.