Using E39 wheels as a winter set? Load ratings?
 

I've got the option to buy a used set of 18" Breyton Inspirations tomorrow in E39 fitment (74mm centerbore and presumably low/middle offsets. I think clearances would work but supposedly these aren't load rated for something as heavy as the X5. I would like to use these as a winter setup and will be ditching the E39 sized tires

How do you know if an aftermarket wheel is load rated to suit something heavier such as an X5?

From my 2 month job, way back in the dinosaur period, I recall some load rating warnings, eg this vs my fading memory:
MAXIMUM LOAD RATING & MAXIMUM TIRE DIAMETER

It is recommended that the load rating of a wheel as determined by the wheel manufacturer, either by a stamp on the actual wheel or in the wheel manufacturer's literature, never be exceeded. If such a load rating is not available, it is recommended that the wheel not be used on vehicle. Wheel load rating requirements are determined by dividing the vehicle's heaviest gross axle weight rating (G.A.W.R.) by 2. The axle weight rating for most vehicles is shown on the identification label located on driver's side door jamb, gas tank door, trunk lid or glove compartment. REGARDLESS OF THE TIRE'S MAXIMUM LOAD RATING, DO NOT EXCEED THE MAXIMUM LOAD RATING OF THE WHEEL.

Back at the Aftermarket Wheel Ranch, I suggest hitting that wheel mfg'er site and seeifn if that list it...or the E39 Boards.

Maybe some Mavens here, can add more...
GL, mD

Should not be an issue. I run 680kg rated ///M3 aftermarket wheels. That limit is reached with 4 passengers and luggage, when I tow with the X loaded or long distance hwy tow the OE wheels/tires go on.