X5 wheels on an X3 ?

[Boyce]

Guy's I've had a search but can't find the info I'm after,

Here's my problem, I have a 2005 X3 2.0 SE, and have fitted a set of used X5 wheels. They have been on for a few months now and I have noticed some slight rubbing around the inner front wheel arches. Closer inspections shows this occurs at full lock only, and there is also rubbing on the struts again only light, and only from tyre contact not from the rim.

The front wheels/tyres are 9J 255/50 19
The rears which are ok are 10J 285/45 19

From the X3 brochure I see the 19" wheels BMW supply are slightly narrower as follows:-
Front 8.5J 235/45 19
Rear 9J 255/40 19

So I guess the question is, can I fit the narrower X3 19" tyres to the X5 rims I have. Could I just do the fronts (as the rears are ok) or will this mess up the rolling radius and compromise the diff's.

Do I have any alternatives ? does anyone supply a small spacer for the front say about 3mm ?

Any guidance/advice greatly appreciated,

Mark.

[Boyce]

I see you can get universal 3mm wheel spacers for about £10, anyone used and have any experience with these ? are they safe, can the standard bolts be used,

Cheers

[davidd]

Fitting narrower tyres should not affect the rolling radius, I would suspect that would upset the geometry of the car less than spacers.

Might be worth having getting the alignment sorted, or see if there are any BMW specific settings for your car with that wheel combo..

D

[Boyce]

davidd said:

Fitting narrower tyres should not affect the rolling radius, I would suspect that would upset the geometry of the car less than spacers.

Might be worth having getting the alignment sorted, or see if there are any BMW specific settings for your car with that wheel combo..

D

Thanks for the reply David, the narrower tyre reduces the rolling radius by about 20mm not sure how significant that is though. Maybe fitting the 3mm spacers at the front and then setting the geometry up would be the answer ? Called BMW they were not much help, just said X5 wheels don't fit X3's !! Buyer be ware!!

[davidd]

Boyce said:

davidd said:

Fitting narrower tyres should not affect the rolling radius, I would suspect that would upset the geometry of the car less than spacers.

Might be worth having getting the alignment sorted, or see if there are any BMW specific settings for your car with that wheel combo..

D

Thanks for the reply David, the narrower tyre reduces the rolling radius by about 20mm not sure how significant that is though. Maybe fitting the 3mm spacers at the front and then setting the geometry up would be the answer ? Called BMW they were not much help, just said X5 wheels don't fit X3's !! Buyer be ware!!

I am getting confused, the rolling radius is the measurement from the centre of the wheel (hub) to the edge (road). How can putting a narrower tyre on change this.

When you say narrow do you mean height? Or do you mean section width?

Cheers

D
(confused)

[[TW]Fox]

It changes the rolling radius becuase the sidewall figure is expressed as a percentage of the width of the tyre.

[davidd]

[TW]Fox said:

It changes the rolling radius becuase the sidewall figure is expressed as a percentage of the width of the tyre.

Ah yes, I understand.

Thanks

(confusion over)

D