Hi

I have a Garmin GPS that I use in my 2008 Toyota Hi Lux work ute.

According to speedo in the GPS the Toyota speedo is way out, at 110 kph indicated on the GPS speedo, while the Toyota speedo reads 120 kph.

Anybody have any thoughts?

Steve

The GPS should be accurate at speed

I've got numerous GPS units, and they all seem to agree with each other......

iv got a garmin nuvi 250w and have tested it in several cars against the speedo.

in a '06 falcon XR6 @ 60kph gps indicated the speedo was at 68kph

in a '07 mitsubishi express van @ 60kph gps indicated speedo was at 74kph, @ 100kph gps indicated speedo read 121kph

in a '03 mitsubishi magna @ 60kph gps indicated, speedo reads 54kph, @100kph gps indicated, 108kph

on a '06 520hp turbocharged nitrous suzuki hayabusa on a certain stretch of freshly laid bitumen @ 250kph gps indicated speedo read 251 kph. (i wasnt riding it...bugger that ! )


i also used a navman 610 widescreen at the same time in the falcon, magna and van and both GPS's indicated the same speed. the garmin is a bit slower to update the speed though.

oh i forgot to mention, after 39 years my beetle's speedo is spot on ! from 0kph to 130kph !

The only minor problem is when they loose satellite connection they just guess, e.g tunnel or heavily treed area you can be doing 100 then slow down to 20 and it will just assume your going 100 all the way (untill its next update)

oh i forgot to mention, after 39 years my beetle's speedo is spot on ! from 0kph to 130kph !
Yep, I had a car once that took nearly that long to get there.
My Garman Nuvi reads 3kmp faster at 70 on the speedo of the Crewman, at 100 k on the Crewman speedo the Garmin reads about 104, so I drive by the Garmin (can no longer afford to get sprung, on a good behaviour licence)

The gps is correct our Toyota Hilux is out the same as the car is made in Tialand what do you expect..

Only out huge like this in our Toyota. Other cars are only out by a couple of klms.

Haven't you noticed people going past you before you got your gps. As when your doing 100 on your speedo your really only doing 90 so your'll never get booked for speeding.

yeah the subarus and some toyotas are out by 10kms on purpose, something to do with speeding prevention.

They make them about 10% out. The ADR's allow up to 10% on the speedo. The funny thing is the ADR for the odometer has a finer tolerance, so the odometer is more accurate than the speedo. Bikes are notorious for incorrect speed readings.

out of over 8 speedos none of my dubs have ever had an inacurate speedo but thats only with the right rolling diameter tyres
worst they are out is no more than 1-2kms
the odometers on the otherhand.... dont think ive seen one thats right

i think its cos there cable drive nothing really to go wrong
cars now are all electric- u can turn off ur ignition driving and the speedo stops working
bad voltage, dodgy sensors etc would give dicky readings

classic example, a mates fairmont crapped its alternator a few weeks ago,
he slowed down for a 60km/h speed camera and his speedo stayed on 110km/h

Hi

Thanks for the replies.

When my son was learning to drive we fitted a digital speedo to his L bug/1303 that runs of magnet on the front hub. Its setup via a menu using the tyre diameter, at 100kph on the GPS its only about 2 or 3 ks over, so I'm fairly happy with its accuracy.

While my son was on his Ls we would often get scowls from other learner drivers if we overtook them, as they probably thought we were speeding when in fact if they were paying attention they were under the speed limit.

I would rather have my speedo spot on and then if I get booked its my fault.

Steve

GPS will be more accurate everytime , tyre wear will throw out your speedo reading.
i have a 2008 toyota hiace with a navman in it , the speedo reads 10 kph faster than the navman at 100kph , all the GPS has done is make me go faster ,that and i no longer look at maps

So your car reads that you have travelled more than what you have so you get your car serviced more eg. every 10k you do you have really only travelled 9k so every 100,000k you have really only travelled 90,000k so you miss out on 10,000ks of your warranty now I know why car companies do this. and it also gives you a false fuel economy reading when you work it out as well.

Ohh and apparently the new adr's, speedo must read between 0% and (+10%+6km/h). In other words they can't read slower, but can read 10% plus another 6km/h over (116km/h reading at 100km/h is acceptable)