Tyre Issue

[Ronniebiggs]

Hi everyone.

I need youir advice.

I have just checked all my tyres and they are all on the limit!

The strange thing is that 1 tyre on the back was a year old and the other rear was about 6 months old. They appear to have worn only half of the thread from the side to the middle but they have ran the thread smooth (outside edge to the midddle) which is strange!
The front 2 tyres where the only tyres that where not new and they seem to be running the outside edge easier than the inside edge but overall I think they could be right as they where not far from the limit when I got the car over a year ago.

Why would the tyres wear like this on the rear?

One tyre was a stunner (yes I know there not great)
The onther was an Avon
The 2 front where the same michelin

All tyre sizes where the same 205 50 16 I believe (May have been 55, but defo all the same profile). I have no bearings off and no bumps or banging noises etc

Im thinking geometry, but I cant understand how it would be out.
Im in a position now where I need 4 tyres and im thinking to I finally take the plunge.

Can someone confirm if 235-35-18 tyres catch on lock or on the rear with a car full?

Many thanks
Andy

 

[BahnStormer77]

What car have you got (year and spec)?

Really is best to have all tyres the same, or at VERY least a matching pair on the front and a matching pair on the rear - preferably matching wear AND make/model of tyre.

Somebody may have skimped and bought narrower tyres for yours at some stage: 205/55/16 isn't right*. I'm pretty sure they should be 215/55/16, but these are more expensive than the 205 wides, hence why people skimp thinking "well they're only a bit narrower", but that's NOT the only difference: the tyre profile is a ratio relating to the tyre width, so 205/55/16's have a lower rolling radius than 215/55/16s... meaning you've actually affected the whole gearing of the car and the the rolling radius is about 4% out compared to what it should be:
1) yes, this means that the odometer is out: e.g. at 103k miles indicated, the car has actually done <100k...
2) it puts your speedo out and changes your gearing slightly (although this will have been balanced against lower drag and resistance)... but at 55mph indicated you're probably doing 50mph...

18" alloys should have either 225/40/18 tyres (which I THINK is the S-Line spec) or 235/40/18's - which is the S4 spec and works absolutely fine on my A4 Sport (which is 30mm lower than SE/standard spec)

235/35/18's will DEFINTELY not catch / lock.... but that's because they are siginificantly too small... 235/35/19's will probably be okay (not that I've checked)... but if the alloys you are looking at are 18's, then you need 40 profile....

 

[BahnStormer77]

Check out this table of tyre sizes from Toyo (I've trimmed it down to the relvant tyre specs - see the link for the FULL table):

 

[Ronniebiggs]

Thanks Lostbok thats exactly the reply I wanted.

I made a mistake the tyres on offer are 235-40-18. I believe the rim width is 8.0 which accoding to your table is listed for that size but it does have 9.0 in bold which im assuming means that, that size is the prefered wheel thickness and its still fine to use a 8.0 wheel.

Only problem im having now is the tyres im been offered are terrible. They are called tiveli and i read loads of bad things about them. So im giving them a call to try and organise some better tyres.

Andy

 

[BahnStormer77]

8.0 is still fine: those are just the recommended and ideal wheel widths for those width tyres... I'll go and check but I'm pretty sure that 8J is the standard S4 alloy width and I know 235/40/18 is the standard S4 tyre spec.

I assume you're looking at buying 18" replica alloys with tyres... there's a reason why they can sell 4 x wheels & tyres for less than you can get 4 tyres.... they're normally very, very poor quality tyres... or at very least very, very unknown tyre makers.... usually those delas will offer you something that's pretty reasonable for a little extra - if that's not already advertised on their site, then call them up and ask them what the options are, but if it's not advertised, then the chances are that they don't get them in bulk, so it won't be a good price.

235/40/18 or 225/4018 are perfect for an A4 (I'd recommend the 235mm wide ones, if you can get them).

 

[Ronniebiggs]

Thanks im ordereing them with the 235's and paid more for some nexen tyres.

thanks for the help

Andy

 

[Ronniebiggs]

I wont need to lower the car will i? its the sport model so it should look ok?

 

[BahnStormer77]

doesn't matter: SE or Sport suspension will be fine... the height of the car should remain compeltely unchanged.... you can probably still lower it a bit if you want to, but hardly necessary: Sport suspension is already 30mm lower than SE and any lower from there is bound to give your insurance company a fit!

 

[Ronniebiggs]

Youve been a star lostbok. Thanks for the prompt replies. I was making the decisions based on your answers.

Many thanks
Andy

 

[BahnStormer77]

I was making the decisions based on your answers.

eeeeek.... pressure

No worries - those tyre sizes should be spot on (exactly the same as mine on my Quattro Sport)... I can't vouch for the Nexens, but presumably a tyre make that you're happier with.

 

[quattrojames]

Sport suspension is already 30mm lower than SE

Its actually 20mm just to keep things accurate.

Changing from 16" to 18" wheels will make the car appear that it is riding higher on the suspension. It is of course totally optical, but something to be aware of. The Sport will probably carry it off better than my SE did.

 

[BahnStormer77]

The Sport will probably carry it off better than my SE did.

huh??!? I thought yours was an All-Road?

 

[quattrojames]

huh??!? I thought yours was an All-Road?

Is that splitter on straight?

 

[BahnStormer77]

Is that splitter on straight?

oh yeah.... bvgger... erm.... darn.... won't let me edit that any more... too late