Fitting different profile rear tyres to 520d

[matt21]

After 31k my 2019 520d Touring is finally ready for new tyres. The fronts are only half worn.

I would like to get the same again, Michelin Runflat Primacy 275/35/19, but finding this size very expensive. Would there be any issue with fitting 275/40/19?

Thanks

[rassi]

If you have an xdrive it is a no go, as you change the rolling diameter between front and rear, and even if RWD then the traction control might play havoc. You should keep the same rolling diameter front and rear, to keep the systems happy

[d_a_n1979]

matt21 said:

After 31k my 2019 520d Touring is finally ready for new tyres. The fronts are only half worn.

I would like to get the same again, Michelin Runflat Primacy 275/35/19, but finding this size very expensive. Would there be any issue with fitting 275/40/19?

Thanks

No can do

Use: https://www.willtheyfit.com/ tyre calculator to see what you can/can't do

You need to keep within the 2.5% +/- tolerances for speedo and diff; but as said above, it's more paramount with xDrive cars

The alternative is to drop to 18" alloys for more sidewall/ride comfort and cheaper prices. But then again, they can be just as expensive

[Pica-Pica]

Stick to what the door label says.

[Mr Tidy]

I wouldn't consider it on an X-drive but it may be OK otherwise although I'm not familiar with newish models so don't know if it might upset some of the electronics.

But I put 255/45 x 18 rear tyres on my Z4M Coupe a couple of years ago instead of the factory 255/40 x 18s for a bit more sidewall (and hopefully ride comfort) and haven't had any problems - if anything it has made the speedo more accurate!