There are several moving parts either on, or attached to the front strut and as it's subjected to a relatively hard life, failures do occur.
The bearings in the top mount can wear – leading to notchy steering, unusual noises, and wayward handling.
Coil springs can crack, again causing knocking noises and odd handling. Shock absorbers can leak, or decrease in performance over time, and pretty much any component that 'moves' in some way will wear out eventually.
Balljoints and bushes in particular can fail and require replacement. In some cases these can be done with the strut 'in situ' but for some repairs the strut must come out.
To replace the shock absorber, top mount, or coil spring you will need to use a spring compressor.
These are straightforward to use, but care must be taken as they are under a great deal of pressure, and failure of the compressor can have catastrophic consequences!
Tools you need replace a front suspension strut
Depending on the arrangement on your car, there are a variety of tools you may need.
But in general you can remove most front struts with a decent tool kit. Be aware that most of the bolts will be VERY tight, so a small 1/4in ratchet set may not be man enough for the task.
A pry bar, or ball joint splitter may also be needed to prise the control arm and track rod end away from the bottom of the hub. Some set ups feature Torx bolts too.
So if you've not got any Torx bits, check to see if your car has them before starting work.
If you need to take the strut apart then you will need a spring compressor. These either come in the hand-held variety, which you hook over the spring and 'wind in' to compress the spring, or as a stand alone unit which the whole strut fits into.
Whichever you opt for take care, as there is a LOT of potential energy stored in a compressed coil!
How to extend the life of a front suspension strut
There's not a great deal you can do to prolong the life of your front struts and associated components.
They will gradually decrease in performance over time regardless of what you do – but giving everything a regular visual inspection can catch potential problems before they become more serious.
Also - always investigate unwanted knocking, banging, creaking or scraping sounds that occur as you drive.
Ignoring one issue could lead to others. Similarly if you notice a shock absorber leaking, replace them (always replace in pairs across the axle).
It's also worth mentioning that 'overworking' the suspension can shorten its life – so avoid thundering over speed humps, or hurtling along unpaved, or badly surfaced roads!
How long should a front suspension strut last
Coils and shock absorbers should give many years of trouble free service, with many cars running on their original coils for decades.
Often the only time these components are replaced is when they either fail, or are flagged up on the MoT test.
But it's worth remembering that old/worn suspension can affect not just the handling but also your braking distances.
So if your car is getting on a bit consider refreshing the front struts, with new dampers and/or coils.
Bushes should also be replaced whenever deterioration is identified, and always when they have failed.
How much does it cost to replace a front suspension strut yourself
As long as you have a decent tool kit, then replacing front struts isn't an expensive undertaking.
Replacement parts vary in prices with an average damper costing around £40. It's not a particularly easy task, as many of the parts are likely to be very stubborn.
Removing ball joints, can be tricky, plus the damper is likely to need a fair bit of 'persuasion' to remove if from the hub/knuckle.
It's one of those DIY tasks where you're better off knowing exactly what's involved before attempting it, and one where an experienced assistant is invaluable if it's not a task you've undertaken before.