89tejpn

My car is an 89 300te. I've had it a few years and it's had a persistent quirk that no one has been able to figure out so far. Now that I'm selling my car, it's more relevant to me to know what's up with it. After the car is warm it will start making a periodic "puffing" of air noise from the right rear suspension. I know it has the self-levelling set-up with the spheres, and I thought it might be a leaky or bad sphere but the ride is excellent and the car stays nice and level no matter the load. There is some smearing on the hydro struts and the left one was replaced a couple years ago. It's like a minor version of the noise a bus makes when it releases air pressure. I have noticed the car seems to be riding a little higher in the rear than in the past -maybe a half inch and it does wallow a bit on the highway. The car has 132,000kms (about 80,000m) Any ideas? thanks