Question about tires size

[Folowiz]

Hello guys,

I have just bought a new to me XC70 (2006) and I am looking to know if the following tyre would work.

At the moment I have some summer tires size 215/65/R16, the OE size basically.
But I Have also kept a full set of wheels with winter tires size 205/60/R15 brand new from a Volvo V50.

Size difference is huge (around 8,7%), but I want to know of that would be OK to run for a trip to Ski station of around 1500km total ?

My main concern is 4x4 system, but it should be ok if all 4 tires are the same size ?

Of course speedometer would be incorrect.

Do I risk something for you guys ?
Thanks

[stuart bowes]

first thing I would find out is do they fit over the brake calipers, if not the question is moot

[Folowiz]

Great question, and yes they do fit, I have already checked.

[stuart bowes]

well that's a good start then lol

I wouldn't be in a position to advise further I just thought that was worth checking first

I suppose also check the weight and speed ratings of the other tyres (maybe obvious)

[SnineT]

PCD should be checked.

MPG might use more.

Insurance company will have to be notified under modifications.

Might not look pretty.

[Folowiz]

Originally Posted by stuart bowes

well that's a good start then lol

I wouldn't be in a position to advise further I just thought that was worth checking first

I suppose also check the weight and speed ratings of the other tyres (maybe obvious)

Speed and Weight all OK.

Originally Posted by SnineT

PCD should be checked.

MPG might use more.

Insurance company will have to be notified under modifications.

Might not look pretty.

PCD same so OK.
The pretty look, don't care, it's just for this trip.

Real concerna again would be to damage anything related to 4x4 transmission ?

[SnineT]

Originally Posted by Folowiz

Speed and Weight all OK.




PCD same so OK.
The pretty look, don't care, it's just for this trip.

Real concerna again would be to damage anything related to 4x4 transmission ?

If you have tyre pressure monitoring I think it'll sort itself out, if not I still don't see any issue if all 4 wheels are the same size, if you had 70's jacked back on the car with 20's on the rear and 15 's on the front, could be an issue.


Just bang the equation into Google as someone somewhere has asked this question before and the answer should be there.

[100K+]

Is not the XC 70 not just a fwd until the 4 x 4 setup is required. Haldex clutch system and all that?? You could drive all the way there and back and never need/use the AWD.. 99% certain you will Haha but the Haldex don't care what size wheels you have on, nor will the software. Smaller wheels will make the car thinks its going faster .. thats all I suspect, which you have already hit on. Jobs worth insurance company would be biggest headache I'd suspect.

Cheers
Bob

[Ripmax]

I cannot stress how important it is to ensure that ALL FOUR tyres are perfectly matched.

Maybe more of an issue on the R as I think this does some fancier stuff with the software meaning the AWD is engaged a lot more often, but the driveline (except engine of course) is identical to an XC70.

[Folowiz]

Ok so you are all making me more confortable.
I have those 4 wheels and the 4 tires have been putted on the same time (they are almost brand new so I guess no problem on that).

Now I just to try I think