Boge shockers - are they noisy?

[B92 8NW]

2 mates of mine have D1s and comment that the OE boge shockers are relatively noisy. I have the original Boge shockers on my current Disco and have to agree that they are a bit noisy... going over speed humps etc, very distinct "sssssss!!". Are they a noisy shocker by default or does this indicate a fault?

[Dougal]

It's a normal noise for an emulsion shock where the air and oil can mix.
Most aftermarket shocks seperate the oil and the volume compensator (sometimes a foam cell, sometimes pressurised gas) so you don't get the same noise.