I think my 1995 Primera is running on the original dampers. It has covered 95,000 miles. I have owned it from 65,000 so I can\'t be 100% if they have been replaced or not.
The car no longer feels \"right\" and I suspect the dampers are to blame. On examination the springs look fine and there are no leaks from the dampers. (I wonder if the springs were replaced before I had the car because they are not corroded and look quite new)
Do I replace the front and the rear dampers only but not the springs?
Do I replace the fronts or the rears only?
It could become costly if the all 4 dampers are worn.
Incidentally, I have done the \"bounce test\" and they don\'t continue to bounce!! But they were stiffer when I first bought the car.
Are there any other tests I can perform?
Thanks in advance
Paul
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They will all be a bit worn and so softer than when new, but probably still legal. I\'m sure you could get a set of \'pattern\' dampers at a reasonable price. Try Brown Brothers. I had a set of their \'own brand\' dampers and they turned out to be made by Boge - a very good brand.
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Ppaul
Aprilia is right. Dampers can lose their performance without showing problems such as external leakage. The bounce test is little use as it doesn't subject them to anything like the loading that they experience when the car is being driven. It's a very simplistic test which will only identify units worn to the point of being dangerous. It's generally reckoned that the effective life of dampers is 80 to 100k miles, at which point the dampers will be worn enought to be having a definite effect on the car's handling. As you've already noted a loss in performance, it's likely a damper change will produce a very noticeable improvement. The springs won't need changing - they may feel softer, but that's because the dampers are not controlling their movement properly.
Regards
John S
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Shock absorbers, my favorite subject!
As correctly noted above, the bounce test is of no real use. It's just to know whether your shocks are dead or not.
You really need to observe your car's behavior when driving it: does it "float" when going fast? Are the wheels all over the place when driving on roads with many potholes? Is the whole car all over the place when cornering on such roads?
Answering "yes" to the above is a sign that your shocks need changing.
Now, you can use the same OEM shocks, or prefer something from a third party. I personally favor Bilstein, although they are more expensive and give a harder ride. But does my clio corner! :->
Vagelis.
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You may also find that the mounting bearings and anti roll bushes have degraded, so don't be surprised if your bill is higher than expected.
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Ppaul,
as already stated, the bounce test as used in the MOT is next to useless and will only pick up something that is already very dangerous rather than underperforming. Did I read somewhere that they have a much more sophisticated shock absorber (s/ab) test in the ROI MOT, a test that properly measures the response to a dynamic input?
The proper way to test your s/ab is to remove them for testing on a test rig.
However, failing that, something you can do yourself is to remove them and carry out the following procedure that I use for when testing my s/abs [1]:
[a] With the s/ab in an upright position [2] move it through the full range of travel up and down three times. This will bleed any trapped air.
[b] Now repeat one more time and note:
[i] resistance throughout the stroke compared to the correct new genuine s/a (crude test of valves),
[ii] any localised changes in resistance, e.g. stiffer at a certain point (test for obvious guide probs),
[iii] any air gap at the top of the stroke should be tiny/ less than 1 cm. (test for leaks).
If your s/abs are indistinguishable from a new one in these respects then I would suggest they are still performing adequately for your 1995 model vehicle and your money would be better spend elsewhere.
PS I had a newish Bilstein s/ab on the rally Range Rover seize absolutely solid, something the other assorted 6 s/abs have not done since/yet. Having said that Bilstein do have the best reputation.
[1] not advisable if you have any back problems.
[2] use a metal bar connected to the lower mounting point to hold it on the ground with your feet.
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Just a point of information, The ROI MOT (called the NCT over here) dynamic test checks the shocks for balance. Taking the back shocks for example, there is a max of 30% (if I remember correctly)imbalance allowed; i.e one shock can be 30% stiffer than the other and the car will still pass.
This is shocking considering that a car will fail if the indicator lens emits light that is not 'amber' enough in colour.
MPH
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MPH, how do they carry out the s/ab test in the NCT?
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The car is driven into a test area and the front and rear axle shocks are tested separately. So, to test the back shocks, both wheels on the back axle are positioned on vibrating plates, built into the test area. These plates are then activated one at a time and measurements are taken by sensors built into the plate's mechanisms
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