Its only the weight of the car that holds them in place
Jack it up and they drop an inch or more
Jack it up and they drop an inch or more
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Technical Top front suspension mount failures
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The cups fitted underneath the strut retaining nuts are there to stop the strut dropping out when the car is jacked up.
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In my experience a failed top mount will result in a suspension twang when going from lock to lock. That’s extra torsion on the springs as the top mount isn’t allowing proper rotation when the rack is moving.
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This happens when the thrust bearings seize up. The rubber mount is probably OK but I have not found a source of bare new bearings supplied without the rubber mounts.
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Correct
SKF bearings are available separately, and seem to be better quality than the ones in cheap complete units.
Can't find the part numbers at the moment. 100hp ones are different, all the others seem to be the same (not sure about 4x4s)
I usually swap complete top mounts as the rubber has a hard life, but the separate bearings are definitely available.
The top mount is not fixed into the car, it just stays due to weight of the car. There is a large washer on the top, which stops it falling out.
I'm guessing the stands are under the chassis/body of the car, not the suspension arms. The strut will have then dropped to sit on those washers, and if lifted, you can lift it back into its fitted position. This is normal and not indicative of any fault. It does still cause some MOT testers to wrongly fail these and other similar vehicles.
The rubber of the top mounts does fail with age, but slowly of course. Difficult to test, with it not being secured, but with the weight of the car on its wheels, it needs a visual check from the top to see if they 'look right'. They should at least both look the same. Height differences, or one being furher back than the other are good indications of a replacement need. With the car on its wheels, pushing down on the wing and watching the flex can also be an indication of its condition.
Some Mot testers are not as experienced as others regarding how cars are jacked up and the effect it has on the suspension and joints etc. Many years ago I worked as foreman at a garage where we were all MOT testers , it saved you dying of boredom just testing all day. In this case the guy doing the testing failed a car on a brake fault and I put it on a ramp for repair and noticed excessive play in the suspension swivel, he replied he would check it when the brakes were done, which he did and called to me saying "what are you talking about there is nothing wrong with it" I took one look at where he had jacked it up and said "you silly **** you have jacked it up in the wrong place" I then showed him that the vehicle had torsion bar suspension so if you let it hang it took all the slack out of the joints, hence no noticeable wear!
My friend has a saying "You can't put a price on knowledge"
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You have to watch garages and tyre fitters for how they jack up Fiat Pandas. Many will shove a jack under the sill and be done with it. Next time you want to jack it up the tyre jack wont fit and the whole area has gone rusty. Make yourself a pair of thick wood blocks with a slot cut across the grain to sit around the sill flange. Make sure they use them.
