Steering & Suspension: Fitting tips

KNOWLEDGE IS POWER

All the horsepower in the world is reduced to nought, if the tyres are not kept in contact with the road surface. Investigating how technicians can hone their skills, Rob Marshall teases out the latest advice.

Any technician that thinks the small but growing presence of high-voltage machinery means that their career will be over soon need not worry. Steering and suspension components are one of the few areas that remain relatively unchanged by EVs, although garages must still be aware of the subtle differences that exist.

Whether powered by combustion, or electricity, controlled by a human, or not (and we must emphasise that ADAS safety aids cannot be confused as being autonomous), the vehicle will still need to deal with corners and surface imperfections.

Obvious suspension ball joint checks (including track rods) include checking for splits in dust covers and excessive movement. When renewing, First Line repeats the importance of replacing in pairs and using new locking nuts, torqued to the correct setting.

LKQ Euro Car Parts highlights that demand for chassis repairs is increasing due to an ageing car parc and the generally poor state of the UK’s road network. Therefore, workshops have nothing to fear but technicians should not be complacent. Improving your knowledge of how to complete the job to the highest standard and keeping aware of how quality parts brands are evolving, including how to use their catalogues and technical advice, will stand you in good stead.

Top 10 Damper Fitting Tips

1. Hold the piston rod correctly

2. Avoid using old fixings, such as nuts, unless replacements are not supplied

3. Mark points during dismantling to ensure correct assembly

4. Do not introduce extra lubricant into the strut

5. Check and follow all torque figures

6. Never use an impact wrench to tighten new fixings

7. Replace dampers in pairs

8. Prime new dampers, by compressing and extending the piston rod several times before fitting

9. Renew all suspension mounting, bearings and protection kits at the same time as the dampers

Steering rack boots should keep dirt out, not fluid in. Should you find oil leaking out, suspect that the hydraulic rack seals are faulty. ZF adds that service time inspections should include the steering rack boots for condition and security. They also should be renewed in pairs.

When replacing EPS columns/racks, do not forget that many types require coding, or calibrating, so it recognises the straight-ahead position.

Comline reminds us that anti-roll bar links can become bent. One reason for this is strain caused by the driver traversing an obstacle (such as a kerb, or speed bump) with one wheel. Protect bushes from unnecessary stress and premature failure, by tightening the fixings with the wheels supporting the vehicle's weight.

Who to trust?

In recent years, quality and profitable garages have avoided selecting the cheapest possible parts and joining the race to the bottom. Quality and availability appear to be more important, something that we hope a potential recession will not topple. Gradually, EVs are increasing and, while it is true that they also need repairs to their suspension and steering, choose a supplier that is aware of the differences that can occur between ICE and EV versions of the same model.

Generally, trust a decent brand name that insists on OE quality at least. Comline highlights that its parts are reverse-engineered from OE samples, produced in OE-approved manufacturing sites using processes that meet OE standards and backed up by a three-year/36,000 miles warranty. First Line told us that its steering and suspension products are also manufactured to OE specifications and possess a two-year warranty against manufacturing defects. Components from the ZF portfolio come also with a two-year unlimited mileage warranty, with quality assurance reinforced by the company being an OE supplier.

Garages should also ensure any brand has decent support and wide coverage. For instance:

Comline's VRM look-up: https://www.comline.

uk.com/vehiclesearch

First Line's WebCat: https://webcat.firstline.

co.uk/Home

ZF's online catalogue: https://aftermarket.

zf.com/en/aftermarket-portal/services-andsupport/catalog/#/

When checking bushes, Comline advises that you should inspect them not just for movement and perishing but also for separation in the bonding between the rubber and metal components.

Replacing the bush, rather than a complete arm, helps to save customers money. First Line says that the suspension arm bush housing must be both clean and undamaged, before pressing in the new bush. Should you have any doubts, renew the arm. Consider that most suspension repairs dictate subsequent suspension geometry checks, which means a subsequent ADAS calibration. LKQ Euro Car Parts finds that offering ADAS calibration provides an opportunity for independent garages to take market share from franchises and this is an area in which future training should be focussed.

What a lovely pair!

Comline, First Line and ZF concur that garages should replace steering and suspension components in pairs. As the recommendation allows them to sell double the quantity of parts, they would say that, wouldn't they? To be fair, they have a point – doing so preserves handling balance. While it is not illegal to replace parts singularly, you may have to advise customers that it is in their best interest to have, for instance, a pair of anti-roll bar links replaced, instead of one. Not doing so can also be a false economy, which is worth highlighting. Should a component on one side be worn out, its opposing number is likely to be in a similar state.

YOU’RE IN SAFE HANDS WITHKYB

All KYB aftermarket shock absorbers are made on the same production lines, using the same materials, and subject to the same stringent quality standards as OE. Trusted by vehicle manufacturers, you can rely on KYB to provide the same world class quality for your replacement parts.

STEERING/SUSPENSION