**Unofficial Tyre Thread**

Man of Honour
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My dad told me about old 4WD systems that you would need to 'unwind' because the turning radius between the inside wheels and outside wheels would change during the course of a days driving. You'd need to put the car in reverse and unwind the tension. That was ages ago and using simple 4WD systems that were locked in a 1:1 ratio.

You can still get wind up on many 4WD systems which are not full time ones like on the Nissan Navara.
 
Soldato
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My dad told me about old 4WD systems that you would need to 'unwind' because the turning radius between the inside wheels and outside wheels would change during the course of a days driving. You'd need to put the car in reverse and unwind the tension. That was ages ago and using simple 4WD systems that were locked in a 1:1 ratio.

I'm not sure this is true - the Frontera I had many years ago with selectable 4 wheel drive; you drove it in reverse a metre or so to unlock the automatic locking diffs.
 
Man of Honour
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I'm not sure this is true - the Frontera I had many years ago with selectable 4 wheel drive; you drove it in reverse a metre or so to unlock the automatic locking diffs.

Wind up is a thing on some older full time 4 wheel drive systems and many newer not full time 4 wheel drive systems. Most modern pickups/4x4 with selectable 2, 4hi, 4lo you should only ever use the 4WD modes off-road or in a straight line on sealed surfaces.
 
Associate
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Wind up is a thing on some older full time 4 wheel drive systems and many newer not full time 4 wheel drive systems. Most modern pickups/4x4 with selectable 2, 4hi, 4lo you should only ever use the 4WD modes off-road or in a straight line on sealed surfaces.
This is what I’ve read too.

Had a look around the internet to see what the deal was with 4WD tension and I still maintain that Audi and other manufacturers have to design a way of getting rid of AWD tension by default or entire range of cars would be needing repairs and a class action lawsuit would appear.

Given how hard I’ve seen Audi Quattro drivers take a corner on bone dry flat tarmac, it’s safe to say that it has to be idiot proof.
 
Man of Honour
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This is what I’ve read too.

Had a look around the internet to see what the deal was with 4WD tension and I still maintain that Audi and other manufacturers have to design a way of getting rid of AWD tension by default or entire range of cars would be needing repairs and a class action lawsuit would appear.

Given how hard I’ve seen Audi Quattro drivers take a corner on bone dry flat tarmac, it’s safe to say that it has to be idiot proof.

Depends on the transmission differential implementation - apparently the Quattros do suffer wind up just it is so minor it generally doesn't cause any problems/damage within the normal lifespan of the vehicle.
 
Associate
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Depends on the transmission differential implementation - apparently the Quattros do suffer wind up just it is so minor it generally doesn't cause any problems/damage within the normal lifespan of the vehicle.
So then does it really matter if your front tyres are new and your rear tyres have say 50% tread?

Given that your front or rear pair will go bald compared to the other front rear pair, I’d argue that the tread difference between 2 bald and 2 moderately used compared to 2 brand new and 2 moderately used are about the same.

Also, If you can go round a 90 degree corner in a Quattro car at 40 to 50 mph and not damage your AWD system, does a moderately different tread depth really matter?
 
Soldato
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I’ve got 6mm tread on my new (to me) S5. Normally would be okay, but it’s running Conti Sport Contacts which are rebound for poor wear.


In 6K miles or so, will get them replaced. Thinking to go for Pilot Sport 5s, given they’re a sporty but not super high performance tyre. Apparently good on wear.


Anyone got any other recommendations?
 

mjt

mjt

Soldato
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I’ve got 6mm tread on my new (to me) S5. Normally would be okay, but it’s running Conti Sport Contacts which are rebound for poor wear.


In 6K miles or so, will get them replaced. Thinking to go for Pilot Sport 5s, given they’re a sporty but not super high performance tyre. Apparently good on wear.


Anyone got any other recommendations?
I think Goodyear have sorted out their wear rate, so the latest F1 Assy 6 is worth a shout, but I'd just go with Michelin PS5s.
 
Soldato
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Got a nail stuck in my right rear tyre so need to replace it as it’s a RFT.

Always best practice to change both rears even though the left rear side has loads of tread left?

£400 for 2 rear tyres is lovely.
 
Caporegime
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Got a nail stuck in my right rear tyre so need to replace it as it’s a RFT.

Always best practice to change both rears even though the left rear side has loads of tread left?

£400 for 2 rear tyres is lovely.

Thats nothing. I got two punctures within the first 3 weeks of my new x5 in the rear RF tyres which are bigger. £470 each time for a new tyre and I was lucky to find them at that price. I think the local BMW dealer wanted £610 per tyre :eek:

Both BMW and Bridgestone state the tyres cannot be repaired. The sooner I get away from run flats the better!

And I only changed the flat tyre each time, no way was a putting a new pair on.
 
Man of Honour
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Got a nail stuck in my right rear tyre so need to replace it as it’s a RFT.

Always best practice to change both rears even though the left rear side has loads of tread left?

£400 for 2 rear tyres is lovely.

I'm having to do just that, got a screw in my rear left tyre. Annoying as they're PS4S's and have 6.5mm each on the rears, but I don't want uneven wear on a car like a C63 so having to replace both. It can't be repaired either as it's too close to the edge :(
 
Soldato
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Is there any deals on P4S that crop up?

I may need to bite the bullet on replacing my Yokos front and rear before I move into the new house as I am going to be properly brassic.
 
Soldato
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I'm having to do just that, got a screw in my rear left tyre. Annoying as they're PS4S's and have 6.5mm each on the rears, but I don't want uneven wear on a car like a C63 so having to replace both. It can't be repaired either as it's too close to the edge :(
It’s a real ballache. The left rear tyre looks brand new but I’d rather take the hit and change both.
 
Man of Honour
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Personally I wasnt prepared to take a £940 hit - twice. I went with uneven wear. there couldnt be too much wear different in 2000 miles surely?
I guess it depends on the car. A performance RWD car, I wouldn't want to run tyres of two different tread depths, even if it's only 1mm difference. Could potentially upset the handling. Plus I'm sure if I had an accident, insurance could use it as an easy get out clause for paying out.
 
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