Running different tire size in fronts

[blizzak]

Will I break/ruin something by running

225/45/17 + 245/40/17 on front Axel for 1-3 months which was originally 225/45/17 + 225/45/17.

Or should I put them in the back (two 245/40/17) and have front 245/40/17 + 245/40/17 and back 225/45/17 + 245/40/17.

Please advise.

[samger2]

I don't think you'll break or ruin anything, but it most likely will affect your handling. Having one side tire having a different overall diameter should cause a slight pull to the smaller diameter size.

So basically nothing on the car should be damaged, but it'll most likely cause you a small discrepancy in handling and/or pulling to one side.

[slocar]

That's fine. The overall diameter is close enough to not affect the ABS or anything else. 96-99 M3s used that setup stock.

As for what what you want to do ... honestly, really doesn't matter, as long as you don't put wider rubber on the front.

[mryakan]

You have tires of different width on the same axle?:confused
I would expect that to impact your handling quite a bit since one side has 20mm less of contact patch (give or take) connected to the road. I personally would not advise that. Tires on the same axle should always be the same size (width and diameter) expect for temporary reasons such as an off-size spare.