boolla

Hi All,
I took my car into the audi dealer and had them replace my stock 17 inch wheels on my 2007 A4 Quattro with 17inch Alloy Wheels with winter tires (dunlop Sport) which i bought used (used for 1 season).
After putting them on I started hearing this pulsating sound (no vibration) which becomes more pronounced at 50-60 Kmph. At faster speeds the pulsation frequency increases but the volume decreases slightly. When stepping on the brake the noise diminishes slightly as well. I suspect it is road noise, but can't explain the pulsation. I did not re-balance the wheels before putting them on, Could this be the problem?
Does anyone have any idea as to what the root cause might be and is there any reason for concern

nbuckley

I had a similar problem with my Dunlop Wintersport 3Ds (but only when driving on the highway). I rebalanced them after I put my first 1500KMs on them. This helped immensely but I still noticed the pulsating for the first 5-10 minutes of driving each day so I also increased the inflation and inflated them to between 38-40PSI (they are stated as something like max PSI of 51). This got rid of the problem and they now drive smoother than my all-seasons even when going 130km/h (although like 99% of the tires/cars out there, things still get a little rough when travelling on the 407 in the GTA when you are going over 125km/h). I think they need higher pressure than all-seasons because the rubber is soft and forms soft spots (flat bottoms) over night that need to work themselves out. The tires are still smooth at high pressures because the rubber is soft. Also you can run tires at higher pressures during the winter because they don't heat up as much when driving them due to the cold temperatures outside.

It seems that every time I get new tires on an Audi (I am on my 4th set of tires total on 2 separate Audis) they always need rebalanced shortly after being mounted. I am not sure if this is because of my drive style or because of the torque or Quattro system.

boolla

Thanks for that info nbuckley.
I will try increasing the tire pressure to see if it makes a difference.
Good feedback.

Thanks