different wheels and odometer

[itskeyes]

I know in theory that larger or smaller wheels will affect speedometer, however doing my research has led me to a post regarding that speedometer calculations are now sensor and GPS based. However, there are coding sections within the NAV control (37) to adjust for circumference.

I get that up to 10% is allowed for speedometer, but does anyone know how the odometer is calculated? If so, could you link me or cite your source?

Thanks!

[Potatohead_RS3]

I would be highly surprised if anything is done by gps. I can only speak to my previous car (a GTI) but 100% for sure the speedo was about 5% fast and the odometer was actually .5% slow. I did try adjusting the speedo through VCDS but any changes also adjusted the odo by the same amount.

[itskeyes]

gps was speculation, but the consensus was 48 impulses per second from the abs ring to calculate speed. Which means the size of the wheels didn't matter. There is no calibration required for newer cars. I'm just trying to confirm if that is true or not.