These rubbers are hidden behind the covers of the torsion bars, and when you remove the spring plates, there is another rubber behind them, so we are talking about the inner and outer rubber. If you own a Volkswagen Beetle up to and including the model year 1959 or a VW Bus (regardless of the year of manufacture), this is not the case, as the interior and exterior rubbers are identical.
If the car's suspension makes noise at the rear, then in most cases, these rubbers are worn. The spring plate is lowered through the rubber and touches the cover. If you continue to drive long enough, you will need to replace not only the rubbers, but also the torsion bar covers. So, if the rear axle makes noise, check the spring plate bushings and replace them immediately.
If only the outer spring plate bushing is worn, it is advisable to replace the inner bushing as well. If you do not, the new spring plate bushing will wear twice as fast.
Some rubbers are identical in appearance; the difference is in the rubber composition. This is only visible on the small round elevations on top of the rubber. One has two and the other has only one, if necessary, keep the packaging near the bushing so that you can mount the right bushing in the right place.
A-quality rubbers have the right hardness and are of a very high quality, therefore equal to the original. B-quality rubbers are slightly softer in terms of rubber composition, which makes them more comfortable, but in terms of handling, you will have to sacrifice something, in addition to that, they will collapse more quickly and have a shorter life span.
Note : If you own a Beetle or Karmann Ghia with swing axles types after 8/1968 and you have also purchased new Paruzzi torsion bar covers (chrome or black), these use bushings intended for years 8/1960 to 7/1968, so ask for the right silentblock for these covers.
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