2021 RST Speedo Off

[Adamace1]

My 2021 silverado was about 1mph over a GPS. So was my 2017 Impala. My 2010 toyota prius was 1 to 2 mph over my GPS. My 2018 f150 was 1 mph over my GPS. Hope that helps. 

[Adamace1]

13 hours ago, elcamino said:

Handheld GPS apps is only accurate to +/- 20 meters and sometimes can be way off if obstructions block some sats'.

I use GPS at work and it can fit in one hand, it is within an inch of acurcacy vertically and horizontally. But cell phones and cheap car GPS are pretty bad.

[redwngr]

https://www.gps.gov/systems/gps/performance/accuracy/