Hi I just bought a 2007 S60 Turbo. The guy that sold it to me told me about the noise, and said it only happens sometimes.

The first couple days I drove it (only short distances), I didn't hear it, but sometimes when I'm bringing the car to a stop, there's a "thump" sound and a faint clicking noise and very slight jerking of the car, that I hear at 15mph. When it happens, it always happens right when the needle hits 15mph.

It doesn't do it on acceleration. It usually happens after I've driven about 30-40 minutes, mostly city driving (using the brakes often).
I had a brake inspection a couple days ago, when I got the oil changed. He told me everything looked good. There's no other screeching and grinding noises, and the car comes to a stop easily.

Incidentally, do I need to change the oil filter for every oil change for this car? That's what the mechanic told me. (This is my first Volvo)

The car seems to run very well, except for this. Although, the biggest concern I have is that a couple times, when I've been making a turn and obviously have my foot on the brake, then make the turn, if I am right at 15 mph (on the needle) and go to accelerate after making the turn, that noise happens and then the car jerks hard and the RPM shoots up to over 2000, if I try to accelerate right at the 15mph mark. Then everything is okay after that. So basically, I've been trying to avoid that and making really soft turns. But then again, it only happens sometimes.

Say I've driven somewhere, and I hear the noise, then turn off the car and park, come back, restart the car, the noise doesn't happen until I've driven again for about 30-40 minutes.

Any help?

Thanks