I have a 2106 S60 T5 Inscription Platinum with about 70K miles. We had new speed bumps installed in our community and the first time I drove over one at about 8 to 10 mph, the front end hopped up and on the way down made a fairly loud 'old squeaky mattress spring' noise. I had a guy check and he seems to think it needs new strut bearings. is this a common symptom of bad 'hi-hats'? I tried the steering wheel test in reverse and I'm not really hearing the clunk many people describe. I'll probably get them replaced, but just curious to see if it could be something else.

 

Sounds right to me, but it could be the strut mount or the strut bearing - but I'd also inspect the spring to make sure that the ends have not cracked off and that they are seated properly. I'd also look at the spring when turning lock to lock to make sure the strut is pivoting freely.

https://www.tascaparts.com/v-2016-vo...ont-suspension shows components and part numbers.