Austin997.2

I have to do a very hard right (wheel all the way clockwise) when reversing out of my garage. When the wheel is all the way turned clockwise I hear and not so nice clanking sound from the front passenger wheel well. In my 996 it did this as well.

The car drives fine but doing this reverse move makes a nasty sound. Any idea? Any help is appreciated

ngng

Diff?

Macster

Most likely normal.

The sound comes from the inside front tire scrubbing as the car is backed out with the wheels turned sharply.

The explanation is the inside front wheel/tire is turned at a steeper angle than the outside front wheel/tire. The inside tire doesn't make full contact with the pavement -- you can see this for yourself: more on this below -- and is not as heavily loaded as the outside front tire. As a result the inside front tire scrubs and that is the clanking noise you hear.

This is more pronounced with heat cycled tires, slick pavement, cold or damp weather. It can happen with the wheel turned in either direction or the car going backward or forward. It can happen at higher speeds under special conditions: Full lock turn on less than ideal pavement and worn/aged tires.

If you want in an empty parking lot park the car with its front wheels turned full lock (either direction). Turn off the engine.

Get out the car and get down at near ground level and site the outside front tire's contact with the pavement. Then do the same for the other tire. The inside front tire will only be making contact with around half its tread width with the pavement.

Also, with a helper you can probably film this happening as you back the car out of the parking lot.

If you want to go to the trouble, scatter about some white chalk powder then back the car up. The images of the front tire treads in the chalk powder I think will make it clear what is going on.

Last but not least if you hear or feel anything else out of the ordinary at any time the car is moving at any speed, in any direction, with the wheel straight ahead or turned in either direction that may not be the same thing and you need to investigate the cause.

Wayne Smith

Good explanation. You will also see that the inside tire looks low on air pressure when parked full lock. For anyone with OCD, this is probably good cause to straighten the wheel when parked, especially in cold climates.

Austin997.2

Thanks for the advice.