DRC Goodwill no more

[stu]

Could my car's apparent intolerance of varying tyre pressures (springier tyres) be a symptom of under performing shocks?

It could be an indicator that the damping isn't correct, and you're in some way compensating for that by changing the softness/hardness of the tyre sidewall by changing the pressures?

They're mid-life Vred Sessantas, so nothing too unusual there. I always set the tyres cold to bang-on 38/35PSI front/rear as per Audi guide. If they gain another 6/5 F/R later in the day when the ambient temp rises and I'm driving (not rallying!) a country road then the car feels too springy. I got out yesterday and reduced it back to 38/35 and it handled nicely again. I had to pump them up again after stopping off in York for a few hours as they were cooler again, well down in pressure and probably unsafe. Felt like an idiot in the car park... That'll teach me for being so picky...
So yeah, in answer to your question Dave, in my mind my dampers are less tolerant than they used to be. My theory: if they're lower pressure they damp less; higher tyre pressures increase the ride bounciness; the under performing dampers don't handle it so well. And over-zealous tyre pressure calibrating gives te dampers an easier time.

[PetrolDave]

They're mid-life Vred Sessantas, so nothing too unusual there. I always set the tyres cold to bang-on 38/35PSI front/rear as per Audi guide. If they gain another 6/5 F/R later in the day when the ambient temp rises and I'm driving (not rallying!) a country road then the car feels too springy. I got out yesterday and reduced it back to 38/35 and it handled nicely again. I had to pump them up again after stopping off in York for a few hours as they were cooler again, well down in pressure and probably unsafe. Felt like an idiot in the car park... That'll teach me for being so picky...
So yeah, in answer to your question Dave, in my mind my dampers are less tolerant than they used to be. My theory: if they're lower pressure they damp less; higher tyre pressures increase the ride bounciness; the under performing dampers don't handle it so well. And over-zealous tyre pressure calibrating gives te dampers an easier time.

IMHO if you're having to mess around with the tyre pressures to that extent then either you're driving it on the edge all the time, or there's something wrong with your suspension.

[stu]

Yup. Thanks. My girlfriend fell asleep while I was driving the route in question (think it's called Snake Pass, from Manchester to Sheffield?). The car's getting the DRC re-pressurised in a few weeks - here's hoping it's low and that's solves it. Tracking was fine last summer, I haven't bumped it and the tyre wear is even. If you can think of anything for the techs to look at while they're there? All HO's appreciated

IMHO if you're having to mess around with the tyre pressures to that extent then either you're driving it on the edge all the time, or there's something wrong with your suspension

...or I'm paranoid

[PetrolDave]

If you can think of anything for the techs to look at while they're there?

Just the usual DRC stuff - low system pressure, signs of leaking, noise from the suspension or valve block,...

[adsgreen]

Just reading the docs and audi say that every time the drc pressure kit is hooked up the system will lose 0.3 bar...

[stu]

Just reading the docs and audi say that every time the drc pressure kit is hooked up the system will lose 0.3 bar...

Yes, the workshop manager said that in his email this afternoon and recommended having the system recharged which I said yes to. I'm glad he's reading the docs as well

I'm wondering if there is a bit of sloppy technique factored in as P_G's is always at 14 and he said he got it measured a few times. edit: misquoted P_G. He said in another thread it's been three years since his shocks were done and they're still at 14. My bad.

[P_G]

Yep, they got checked at MOT/service last year becasue I asked and it was 14 so assume it is now 13.7 then. Still not that bad.