GapTool and correcting speed reading

[gavinwibrow]

Anyone care to point me in the right direction?

My D4 speedo reads 5% fast, and if, as I suspect I can, how do I adjust it to read true. I'm aware it won't affect the km travelled.

[Tombie]

Change tyre diameter.

For full advice have a look in FAQ on Gap Site.

[gavinwibrow]

Change tyre diameter.

For full advice have a look in FAQ on Gap Site.



Thanks Mike. I'd read the FAQ twice and missed that both times - new glasses perhaps!

In case anyone else was wondering.

For Discovery 3 2004-2009 and Range Rover Sport 2005-2009
Menu–Car Config–Instrument Pack–Tyre Radius

For 2010+ vehicles

Only one of the following settings will work and it depends on the car itself. Menu–Car Config–Instrument Pack–
This setting, Tyre Size MSB – IPC
Or this one, Tyre Rolling Radius (mm) – ABS

[John_D4]

I put on 285 60 18’s which are 5% bigger than 255 55 19. Fixed my speedo but the odometer is now reading 5% under. Will fix that problem when I buy a gap tool

[Redtail]

Tyre size worked on my 2011 HSE.
Rooling radius made no difference.

See:
https://www.aulro.com/afvb/electronic-diagnostic-systems/262612-speedo-calibration-iidtool.html#post2816084