First let me say I have read these past threads which I found searching "speedometer".
https://g35driver.com/forums/showthr...ht=speedometer
https://g35driver.com/forums/showthr...ht=speedometer
https://g35driver.com/forums/showthr...ht=speedometer

I want to know if anyone has concluded anything concrete or if a dealer can actually accurately reset our speedometers.
I drive an all stock 07G35x with 10,500km on the odometer. The tires which are cold inflated to 35psi are barely worn. I checked the pressure with 2 gauges (one digital).
I checked my speedometer today while driving with cruise on, on a constant flat grade of the 401. The portable GPS read 130km/hr and the car speedometer read 139km/hr. This speed lasted about 2-3 minutes until there was a significant grade change at which point the car slowed for a moment.
I have used the same Garmin GPS unit in my old 03VW, my 07 Honda Odyssey and my friends Ridgeline and the GPS and speedometers always have matching readings. (within a speedo needle width which can't be more than a half click or so)

So I ask you; has anyone bothered to try and get it fixed by the dealer and what are the results. I will be asking my dealer but I wanted to hear from you guys first (to arm myself) so I don’t get a load of BS from them if it’s repairable.

Thanks

 

im actually curious about this because ive noticed my stock navigation is like 1/2 a block behind where my car actually is or is that normal?

 

I got the same results as you when I checked the accuracy of my speedo.
I did nothing about it.
The speedo is out but my odometer seems accurate.

 

My tires are pretty worn, but my speedo reads fast too.

According to my speedo, I'll be doing aroudn 33mph, according to the radar booths the police set up that display your speed, I'm actually only doing around 30.

My next set of tires will actually be slightly taller, so it may fix the problem.

 

it tells you when you first insert the dvd you must drive for like 30 minutes with no electronical devices going a constant 30mph or something so it can locate you accurately.. i never did it

 

The 07+ features a hard drive based navi system. No DVD required.

 

Can we please get back on topic...I am looking for answers about the known speedometer calibration problem , it's not a GPS thread. (no offence)
Thanks

 

Hmm, My 07 "X" is spot on, 9000 miles, on it, and also some hard road racing at rough BIR in north MN. I have checked it againt gps, and all those cop radar stands someone else mentioned... when its 60 its 60 (mph) and when its 130 its 130...

 

Very nice, good to see some folks have an accurate one.

 

Hate to say it, but my '08 is spot on as well from 0-90mph according to my HP Ipaq 310.

 

Off topic, but try checking your Navi to make sure it's set up for the correct region (there are 10 to choose from). Most of the time our cars here in Hawaii are oddly setup with Calfornia as the default (why I have no idea as the cars come here straight from Japan) and the GPS will read off a bit until this is corrected.

 

The speedometer in my 08 G35x reads 3 MPH high regardless of the speed. I checked this with 2 Nav units. I also checked the odometer with the same 2 Nav units and it is reading accurately. It seems as though the speedometer needle is not set at the correct position.

I took it to the dealer to have it checked out. They told me that they checked several cars there and they all read 3 MPH high. They also told me that they checked the service manual and it states that the speedometer can be off by 1-3 MPH. They couldn't make any adjustment to the speedometer and a replacement cluster would also have a speedometer that was incorrect so they wouldn't do anything about it.

I hope you have better luck than I did. Keep us posted how things turn out.