Can't believe you contacted VW about it 
All season tyre question!
- Thread starter Churchy
- Start date
At least if the Haldex drops its guts, he has it in writing from VW.Can't believe you contacted VW about it
That will mean nothing in reality.
"Tried to calculate this back to a tread depth variance. I reckon 2-3mm difference in tread depth would be the max amount to keep the circumference within 10mm"
That would work out at about 0.75mm tread difference.
If you want it more exact I can get down and dirty with an abacus or a slate and some chalk?
That would work out at about 0.75mm tread difference.
If you want it more exact I can get down and dirty with an abacus or a slate and some chalk?
How did you work it out?
Exactly this. Be plenty 4motion, quattro, etc. Running around without any thought about tread depth.
Sorry - that was flippant.
If you had a piece of string around any circle and then another piece of string around a slightly bigger circle (doesn't matter on the size as we are talking arithmetic rather than geometric) then we are trying to get the longer piece of string to be 10mm longer. So - we need to find out the difference in the radius (or how far away the strings are from each other).
2 x pi x r = circumference of tyre (or change in circumference of tyre)
2 x 3 (not pi but easier to play with and if you don't like the result we can calculate it properly) x r = 10mm
2 x 3 = 6
6 x r = 10mm
divide each side by 6
r = approx 1.6mm
However, we don't have tread only on one half of the tyre - it is all the way round. So ....
1.6mm / 2 = 0.8mm
Seeing as pi actually = 3.14 etc etc (8 decimal places might be enough to get you to within 50metres of a specific spot on the moon (possibly - that is another thread for the future), the actual amount of tread would be
2 x 3.142 x r = 10mm
6.284r = 10mm
r = 1.59mm
Divide this by 2 (tread is all around an not all on one side)
0.795mm
Looks like I was way out (6%) on my first post. This is what brandy does. Don't drink it kids. I'll wake up in the morning with a bleeding headache, dehydrated and then realise none of this makes sense.
If you had a piece of string around any circle and then another piece of string around a slightly bigger circle (doesn't matter on the size as we are talking arithmetic rather than geometric) then we are trying to get the longer piece of string to be 10mm longer. So - we need to find out the difference in the radius (or how far away the strings are from each other).
2 x pi x r = circumference of tyre (or change in circumference of tyre)
2 x 3 (not pi but easier to play with and if you don't like the result we can calculate it properly) x r = 10mm
2 x 3 = 6
6 x r = 10mm
divide each side by 6
r = approx 1.6mm
However, we don't have tread only on one half of the tyre - it is all the way round. So ....
1.6mm / 2 = 0.8mm
Seeing as pi actually = 3.14 etc etc (8 decimal places might be enough to get you to within 50metres of a specific spot on the moon (possibly - that is another thread for the future), the actual amount of tread would be
2 x 3.142 x r = 10mm
6.284r = 10mm
r = 1.59mm
Divide this by 2 (tread is all around an not all on one side)
0.795mm
Looks like I was way out (6%) on my first post. This is what brandy does. Don't drink it kids. I'll wake up in the morning with a bleeding headache, dehydrated and then realise none of this makes sense.
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If you're using the radius rather than diameter in your calculations, there's no need to divide the result by 2.
I make it about 1.6mm tread, using 215/60/17 as a nominal tyre size.
I make it about 1.6mm tread, using 215/60/17 as a nominal tyre size.
Yep - you are right.
Nice one
Meanwhile back on planet earth, the official definitive answer is “it’ll be reyt”
New Tyre Reviews all season test summary video out today.
Link
In summary - all season are great as winter tyres in the UK (this isn’t new or a big surprise as we don’t get much snow anymore).
All season tyres still can’t match summer for dry or wet weather (again - no surprise).
Best all season tyres for Europe based on the results of 40 tests are 1) Pirelli Citurato AS SF3, 2) Continental AllSeasonContact 2 3) Michelin CrossClimate 3 sport.
I’ve had the Continental fitted for around 2 months now and am pleased with the comfort and noise. The way I drive I don’t really challenge the grip limits of a modern premium tyre so no worries on that front for me anyway.
Link
In summary - all season are great as winter tyres in the UK (this isn’t new or a big surprise as we don’t get much snow anymore).
All season tyres still can’t match summer for dry or wet weather (again - no surprise).
Best all season tyres for Europe based on the results of 40 tests are 1) Pirelli Citurato AS SF3, 2) Continental AllSeasonContact 2 3) Michelin CrossClimate 3 sport.
I’ve had the Continental fitted for around 2 months now and am pleased with the comfort and noise. The way I drive I don’t really challenge the grip limits of a modern premium tyre so no worries on that front for me anyway.
With a Haldex based always active AWD system you'll generally get heavier wear on the fronts that do the bulk of the traction.
Best plan is rather than replacing them as they wear out swap front and rear sets to even the wear - on my old Volvo it was done every annual service and that went to 250k without any issue with the Haldex.
Personally I'm more concerned about matching depth across the axle than between them.
As a side tip (having run CC and CC2 for most of the life of the Volvo) I found they worked best well inflated the majority of the time but running them at the low end of inflation when there was snow on the ground gave them a bit more grip. Obviously don't drop the inflation to unsafe levels.
Best plan is rather than replacing them as they wear out swap front and rear sets to even the wear - on my old Volvo it was done every annual service and that went to 250k without any issue with the Haldex.
Personally I'm more concerned about matching depth across the axle than between them.
As a side tip (having run CC and CC2 for most of the life of the Volvo) I found they worked best well inflated the majority of the time but running them at the low end of inflation when there was snow on the ground gave them a bit more grip. Obviously don't drop the inflation to unsafe levels.
I completely agree. I ran an AWD XC60 for six years which, when I first got it, was running on summer Continentals. After discovering they were rubbish in the cold even though they were quite new, I replaced them with a set of CrossClimate SUVs. When the tread on the fronts reached 2mm less than the rears I swapped them over. Doing this roughly once a year, seemed to even out the wear. The only downside is that at the end of life all four tyres need to be replaced. The upside is that you get an identical tyre at each corner with identical handling and performance characteristics.
I’ve found that dropping the pressures by 5 psi when there’s snow on the ground definitely gives more traction, and not just on AWD vehicles. That said, having a tyre with a tread pattern and construction appropriate for handling, steering and braking in cold conditions whether wet, icy or snowy is the key to avoiding hitting things or ending up in ditches.
I am always a little perplexed of the results of those tyres test.
They usually test them on a car like a Golf, with similar sizes (but not load index and pressures) as ours. The everyday weight of a converted camper or an everyday van is close to double of that car.
I tend to evaluate higher the few specific van tests or at least heavy SUVs. Heck, I got my Kombi on the scale during this summer vacation and I was at more than 2.8 t.
Sidewall construction and ply layering will make some difference to comfort, noise, fuel economy and handling for sure, but the material blend and tread patterns are still an important element and are very unlikely to change between the different load ratings of a specific tyre. So I still see some merit in the tests.
Over time patterns emerge too - generally the main brand premium tyres out perform the cheap ones by some way - always interesting to watch.
Maybe when people watch his videos they should comment about seeing some tests using camper vans - he does seem to read and reply to many of the comments.
