On the original subject of the shocks and springs. and thinking too about "a crashy ride"
As the springs are most easily assessed I'd be looking at them first. So, first off, when you're out and about, look at a number of similar cars in the street. look at the tyre clearance with regard to the top of the wheel arches front and rear. If the car is parked at the curbside you might risk sticking your fingers in between the tyre and top of the wheel arch as a rough measurement of what the gap is. - be prepared to explain yourself if challenged. However, I've done this in the past and never been challenged. Once you've observed a number of vehicles you should have a good idea of what the typical ride height is for your vehicle so now, park your car on level ground and do the same check on yours. Springs do tend to settle. (our Becky - 2010 Panda - had this problem with her front springs when I bought her. Many of the 169 models I see are a bit down at the front. keep your eyes open when you see one and you'll see what I mean) However it's worth knowing that some manufacturer's models ride a little higher at the rear than others)
Here's a picture of Becky after the new front springs were fitted, see how the wheel arch clearances are pretty much identical front and rear.
Keep an eye out in the street and you'll see many which are definitely down at the front. If it's down then the springs have settled. If just by a little then I'd not be worrying, however if very noticeable then, for this reason alone, I'd be replacing them.
If it passes the "sagging" test then a closer examination of condition is needed. Is the spring pitted with rust - this causes stress concentrations which make the spring much more likely to snap on something like speed bumps and potholes etc. Lastly check to ends of the spring very carefully. every now and then you may find a spring where only a small piece of the end of a coil has snapped off. this may not cause any great difference in ride height so is difficult to see by just checking wheel arch clearances - you need to jack it up and have a good look.
So, if the ride height looks acceptable and the springs are not heavily rusted or otherwise damaged, I'd be happy to continue with them. - inspect for rust very carefully as springs can look good on a casual inspection but have just one small area heavily rusted - perhaps where a stone etc has damaged the protective paint coating and allowed a very small area to become heavily pitted.
Shock absorbers seem to fail frequently these days, probably due to people going too fast over road calming humps or potholes? The "Fast Fit" type stores could probably exist on tyre and shockers alone? By the way, NEVER simply agree to having new shocks fitted at one of these places without getting a second opinion from a trusted source, by which I mean from a friend who is knowledgeable about cars or a trust independent workshop. I've worked in these places and upselling shock absorbers is a well known money maker!
They tend to fail in two ways. Most commonly they'll blow out the top, damper shaft, seal. This is usually easy to see because there will be oil dribbling down the outside of the shocker. Dare I suggest that an oilcan squirted in the right place can give the same symptom? so beware. Also they may fail internally and just not be "resistive" any more - hence the Bounce test Mike was talking about above. Worn shocks can be very dangerous because they let the tyre/wheel "patter" on the road instead of maintaining good contact and this can, in an extreme situation, cause very serious handling problems. So, if there's oil visible or the suspension is overly "bouncy" new shocks are needed.
Less common are problems like bent damper rods, protective covers breaking loose and clattering, and worn rubber bushings.
Now how about the "crashy" ride? Assuming your check of springs and shocks hasn't turned up anything obvious, rubber bushings are an obvious target for attention. suspension arm bushes - on the Panda the rear bush on the track control (lower suspension) arm are wellknown to break up. Anti roll bar bushes can make a hell of a racket when play develops in them as can drop links (another common thing with the Panda). Top suspension mounts are always worth a good look and also worth checking out for worn top mount bearings.
Regarding top mount rubbers. Open the bonnet and check that they both look the same, it's not uncommon for one to fail before the other and you'll see it immediately because the damper rod will be sticking up slightly more than the better one. If looking Ok, now jack up the front until the wheels are just off the ground and place a wee heap - two or three will do - of "glossy" magazines under each wheel. Now let the car back down onto them. The magazines are "slippy" so let you turn the steering wheel without the tyres trying to resist by gripping the road. Now turn the steering lock to lock and listen for "graunch" noises. All quite, probably Ok. Graunchy noises? probably a top mount bearing corroded (might be both so get a pal/wife/friendly passing dog? to turn the steering while you stick your head under the bonnet and locate the noise. By the way, don't worry if you notice that the top mounts drop out of their seatings slightly when you jack the front wheels off the ground. They rely on the weight of the car being on them to push them fully home and will drop slightly when the car is jacked up.
Oh dear, another of my lengthy tomes? anywho, hope it helped someone and can anyone think of something I've missed? I've not talked about ball joints/trackrod ends because they usually cause a knock but not so much a "crashy" ride.
