A4Scott

I've got dynamic steering on my car and I've noticed when going slow (in parking lots for example) I hear a noise coming from the steering column when turning the steering wheel. It's a fairly quiet noise almost as if something is rubbing as it turns. Can anyone with this option comment as to whether you've heard/felt this as well? It may be normal with the dynamic steering but I did not hear this noise on several rental/loaner A4/S4 vehicles (without dynamic steering) that I've had. Dynamic steering doesn't seem to be a very common option so my car is the only one I've driven with it so I have nothing to compare.

Burrcold

It's the ratios changing. Solution...keep it dynamic and it's a fixed ratio

A4Scott

I do keep it in dynamic for most of the time. Are you sure the ratios don't change in dynamic?

Burrcold

They don't. Fixed ratio as soon as it goes into dynamic (steering can still vary in weight but that has nothing to do with the gear ratio change).

adg44

This is not correct. Only the RS models get a fixed ratio with dynamic steering when in Dynamic mode of drive select.

And regardless, you shouldn't hear the "ratios changing" when you turn the wheel. If you are getting some noise, best to let your dealer take a look.

Burrcold

Not true. Both models get fixed ratios when in dynamic, it's just the ratio is different.

Dynamic Steering:

Comfort: Ratio changes with speed from 9:1 to 18:1, speed sensitive high level of assist
Auto: Ratio changes with speed from 9:1 to 18:1, speed sensitive moderate level of assist
Dynamic: Ratio fixed at 14.3:1, speed sensitive low level of assist.

Standard Steering:

Comfort: Ratio:15.9:1, speed sensitive high level of assist
Auto: Ratio: 15.9:1, speed sensitive moderate level of assist
Dynamic: Ratio: 15:9:1, speed sensitive low level of assist

A4Scott

Where did you get this information?

I do have trouble noticing any difference in ratio between the different modes. Should I see any difference when driving very slow, say in a parking lot, between auto/comfort and dynamic?

adg44

Sorry, this is incorrect. Both the ratio range and the fixed in Dynamic mode.

RS models get the ratio fixed in dynamic mode at 13.5:1. But this is unique to Audi Sport models.

Hope this helps.

superswiss

This information appears to come from a post I made a long time ago and is for the B8 RS5. I never found confirmation that the ratios are the same in the B8 S4/5 and if it has a fixed ratio in dynamic mode. For the B9, @adg44 appears to be correct. The fixed ratio is only for RS models and it is also a different ratio from the B8. It's relatively easy to verify. Just check how many turns it takes lock to lock in the different modes. It's very obvious if the ratio is fixed in dynamic mode or not. At low speeds the ratio is very direct when it adjusts and it takes less steering input to maneuver the car, in other words fewer turns lock to lock.

A4Scott

Thanks - yes, I have tried this and it's approximately the same in all modes (comfort, auto, dynamic), about 2 turns lock to lock.