12-10-2023, 01:24 PM | #1 |
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Reverse full steering sudden noise
Hi Everyone,
As per title, sometime during reverse with full steering (during parking), i heard a strong noise with a strat. Has someone experienced the same noise? I’m not sure but it seems happens more with wet road. |
12-11-2023, 08:11 AM | #2 |
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typically happens in cold weather - the Michelin Pilot Sport Sidewalls fold over the tread on full lock !
Search the Threads for a more full explanation ... Here you are I copied some salient sections ... Me: First start of the day - esp in the recent cold spell - on reversing out of the driveway, using anything over half-lock there's a couple of thump/bumps from the n/s front .... bit like driving over cats-eyes ... nothing evident fouling, and no obvious signs of brake-pad 'stiction' .... Doesnt normally do it again after a short drive - and never does it if I reverse into the driveway to park - thus drive straight out instead of reversing the next day .. --------------------- Response: This is due to the Michelin PSS's on the front being 88Y i.e. soft sidewalls and folding over on them on full lock. It is perfectly normal. As the wheel goes onto full lock it tilts (castor angle). This tilt cause the tyre to fold over the edge of the tread which causes a thump through the suspension and steering. I too had the problem you are describing and took the car back to the dealer who gave me this explanation. When I changed the fronts to winters and then onto Goodyear Asymetric 3's when I replaced the PSS's (92Y rating on the front) the knocking was no more. You can reduce the problem by increasing front tyre pressures, I think a lot of people run 2.4bar at the front. ---------------------- another Forum:- It's perfectly normal and correct to hear a ping/twang when reversing on full lock due to the Ackerman geometry. It's literally dragging the tyre, which eventually has to catch up when the force overcomes the sidewall deflection & grip. Both of mine have done it on full lock reverse, always seems much more noticable when the tyres are cold.
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