I'm looking on tire rack at at some different 17" wheels. But some of them have a warning saying "MAY REQUIRE MODIFICATION TO THE REAR PLASTIC FENDER LINER"

For example the OZ Superturismo's which have an offset of 40.

Can anyone enlighten me as to why using these wheels may require modification to the fender liner?

40mm would be slightly further out than stock I think so why would that affect the fender liner?

 

This is all dependent on if your MINI is lowered. IF it is not you will be fine with 40mm. Once you lower it you will run into issues with different offsets.

 

They are just covering themselves. 17x7 et40 is a conservative size, you should have no problems.

 

If you have a later model MINI and use stock suspension you should be fine.

If you lower your MINI and use a tire size that is taller than stock like 215/45-17 then there is more risk for rubbing in the rear wheel arch area, especially over dips and with a full load.

That wheel size is fine otherwise.