Tyres
 

Hi was just seeing what people think I need two new front tyres on my xc90 I currently have Avon htt ranger on all four wheels the rear have 6mm on them but you can’t get these tyres anymore so not sure what to do I can get Avon’s again but not the same ones so should I change all four or will it be fine to put 2 different ones on the front just after people’s opinions thanks alot

Check out the thread "What are the best tyres to put on an XC90 " plenty of info on there for you.

Mixing new and old tires is a problem. Even mixing two different brands of new tires is a problem because not all brands have the exact same external diameter. Worn tires and new tires even more don't have the same diameter and the difference - even small - wears the differential. This is why - unfortunatelly, and little known at the moment of purchase - we have to replace all 4 tires at once on AWD cars, and constantly rotate the tires for even wear.

This is not true for the Hadlex equipped XC90, which is not a differential but a series of hydraulic plates. The front and rear differentials are constantly turning at different speeds as are each of the wheels as they travel at different speeds.

There is no need to change all four tyres. On some AWD cars of yesteryear which had thermo viscous couplings (Vauxhall Cavalier, Land Rover Freelander 1) you could damage the drivetrain if you fitted random tyres of different sizes, but on Haldex AWD cars (all post 2003 Volvo models) this is simply not an issue.

Volvo's belief in the wisdom of tyre rotation is not restricted to specific drivetrain setups. Sampling the online versions of UK Owner's Manuals for vehicles that are AWD (2010my XC90), 2WD or AWD (2011my XC60) or 2WD (2012my C30 and 2017 V60) shows exactly the same words.
To avoid differences in tread depth and to prevent wear
patterns arising, the front and rear wheels can be switched with each other. A suitable distance for the first change is approx. 5000 km and then at 10 000 km intervals.

You don't need four new tyres or even matching brands. The modern AWD system can cope fine with the differences in diameter, all four wheels will be turning at different rates anyway when you corner as someone has already mentioned.

The only real safety issue is to match the tyres on each axle (so a pair of the same tyres at the front and again at the rear). This avoids having different lateral grip properties in each direction.

Thanks for the replies had a read of the tyre thread I think it all comes down to personal choice I’m glad I don’t have to change all four I do prefer 4 matching tyres though will let you know what I go for and how they perform thanks again

Daniel

So went to get two new tyres fitted today two Avon zx7s was waiting at the tyre centre and got talking to an owner of a Range Rover sport and a fellow xc90 owner not sure if he is on here and they both recommended accelera tyres I have heard of them but not used them they had both used them before and couldn’t speak highly enough of them so I ended up having four of these fitted and four wheel alignment done so not sure if I ended up making an expensive mistake but time will tell the drive home was fine and the steering does feel sharper but will keep you updated on how they wear and handle the wet I am going on holiday in a couple of weeks to north wales so will give them a good test but I have got two Avon rangers for sale if anyone needs them both have 6mm of tread with no puncture repairs but will put it in the for sale section

Daniel

I bought a set of 19in sport wheels for my xc90 and one of tyres were scrap and other 3 were ok,

2 of them were a matched set of accelera's with loads of tread on, other 2 wheels i put a set of general grabber GT's,

I put the accelera's on front to run them off and the 2000miles ive done on them and actually been quiet impressed for a budget tyre