Moderator: volvite
My apologies, I meant to say 2-3 slower on the GPS...got distracted and mis-typed...so, same experience. And your reasoning makes sense. Same reason most law enforcement officers won't stop a vehicle for going 5mph or less over the limit...room for error/calibration of the radar equipment & the speedometer. Makes sense...and actually is a little comforting to know the vehicle is reading 2-3 faster than actually moving...LittleStevie wrote:Go with what the GPS says. The vehicle's speedometer relies on assumptions of tire diameter in calculating a linear distance from number of tire revolutions. Treadwear and tire pressure could contribute to error.
I've observed the opposite of Mark, on every vehicle I've seen the speedometer reads 2-3 mph faster than the GPS. I would not be surprised if the automakers do this intentionally for conservatism, to avoid getting sued by someone who says their speedometer caused them to get a ticket.