Common for all 4 suspension arms to need replacing ? 996TT
Discussion
I knew one of my front arms needed replacing - recent OPC service highlighted it.
But I dropped it into a specialist (excellent reputation) for their opinion and they hiked it up on the ramp & they are telling me all 4 need doing as the bushes are shot on all of them. Find this a little odd. Car has done 36k miles.
If it needs doing then it needs doing, but dont want to be ripped off.
An extra thing worth noting, is that the rear tyre wear is very un-even which could suggest that the rear arms do indeed need doing too, thought I would mention it.
But I dropped it into a specialist (excellent reputation) for their opinion and they hiked it up on the ramp & they are telling me all 4 need doing as the bushes are shot on all of them. Find this a little odd. Car has done 36k miles.
If it needs doing then it needs doing, but dont want to be ripped off.
An extra thing worth noting, is that the rear tyre wear is very un-even which could suggest that the rear arms do indeed need doing too, thought I would mention it.
Its certainly possible, as for uneven tyre wear, you won't get even wear anyway on a Porsche, generally wearing out the inner edges first, unless its tracked with too little neg camber then it will be the inner and outer edges.
I would leave the bushes until you can notice a difference in the handling and noise over pot holes, otherwise you are replacing them often at your cost.
If the rear tyres are not a mirror image of each other when used on the road i would get it 4 wheel aligned.
If you use it on racetracks its going to give your very uneven wear for pretty obvious reasons.
I would leave the bushes until you can notice a difference in the handling and noise over pot holes, otherwise you are replacing them often at your cost.
If the rear tyres are not a mirror image of each other when used on the road i would get it 4 wheel aligned.
If you use it on racetracks its going to give your very uneven wear for pretty obvious reasons.
Edited by Pork_n_Beem on Monday 24th September 18:02
Cheers Pork - its the outside edges wearing much more than the rest of the tyre. Car has never been tracked. It certainly needs a geometry alignment, its never been done on the car. And one arm deffo needs doing - I just dont want to have to fork out for 3 more if its not really needed.
Sounds like too much toe but they do need changing eventually and we offer reconditioned arms at a saving.
The problem is that wide tyres with low profiles are stiffer at the edges than the centres (relying more on the tyre pressure than anything else) and as you turn the steering the camber changes (you can test this static) and you can see how the wheel rides up on inner and outer edges as you go from lock to lock. The narrower the wheel the less it lifts and the higher the tyre wall the more it can flex to accomodate the side loading.
The speed and cornering force for that degree of turn affect the weight distribution and therefore which part of the tyre digs in the most. Tyre pressures also influence the wear patterns - too soft could cause outer egde wear.
The standard setting assume certain driving useage and conditions but everyone is different and ideally would have their own settings in a perfect World. Apart from springs gradually sagging (usually over about the first 4 years) resulting in too much camber and toe - it should be possible to work out what is going on and take some steps to improve things.
So you need geometry checks but also the specialist to adapt settings to suit the driver - IF - they have unusual wear patterns that may be put down to their driving style.
Baz
The problem is that wide tyres with low profiles are stiffer at the edges than the centres (relying more on the tyre pressure than anything else) and as you turn the steering the camber changes (you can test this static) and you can see how the wheel rides up on inner and outer edges as you go from lock to lock. The narrower the wheel the less it lifts and the higher the tyre wall the more it can flex to accomodate the side loading.
The speed and cornering force for that degree of turn affect the weight distribution and therefore which part of the tyre digs in the most. Tyre pressures also influence the wear patterns - too soft could cause outer egde wear.
The standard setting assume certain driving useage and conditions but everyone is different and ideally would have their own settings in a perfect World. Apart from springs gradually sagging (usually over about the first 4 years) resulting in too much camber and toe - it should be possible to work out what is going on and take some steps to improve things.
So you need geometry checks but also the specialist to adapt settings to suit the driver - IF - they have unusual wear patterns that may be put down to their driving style.
Baz
Well its booked in for a full geo (£180 ish so not too bad) - considering its a 5 year old car with 36k miles on it and never had it done, then it should be done.
The lower arms I will speak to them about - if they are sure all 4 need replacing then no problem, but in my dealing with this specialist they can be a little "oh if that one needs replacing than the opposit one does too" type thing.
The lower arms I will speak to them about - if they are sure all 4 need replacing then no problem, but in my dealing with this specialist they can be a little "oh if that one needs replacing than the opposit one does too" type thing.
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