GPS V on the highway

[rwinters]

I have a ways to go before I really understand all the features of this unit. One problem is hook up to my Mac or even my PC laptop which does not have serial port. So first I have to get the adapter.

 

But I wanted to know how accurate is the mph indicator on the V. I am reading 4-5mph faster on my speedometer. But I did change to lower profile tires so my speedometer could be off and the Garmin just made that evident.

[+TheCacheCrew]

Don't know the official details, but...

 

The V registers 2.5 mph faster than the speedo on our Xterra. Stock tires and wheels.

 

The V registers 1-2 mph different than the speedo on our Quest, but I don't remember whether it reads faster or slower.

 

Seems amazing to me. I mean, how far away are those satellites again???? ;-)

[+Night Stalker]

I have the Magellan Sportrak and my brother-in-law has the Garmin V. We checked speed with both and they were right on. I suspect that the speedometers are off not the GPS.

[+Night Stalker]

I have the Magellan Sportrak and my brother-in-law has the Garmin V. We checked speed with both and they were right on. I suspect that the speedometers are off not the GPS.

[vagabond]

thats it

 

All who look are not lost

[Couch_Potato]

quote:

---

Originally posted by TheCacheCrew:

Don't know the official details, but...

 

The V registers 2.5 mph faster than the speedo on our Xterra. Stock tires and wheels.

---

 

Odd, my stock Xterra reads about 5% faster than the GPSr. Speedo reads 70 and Legend only shows 67.

 

I'v just assumed that the speedometer is calibrated slightly wrong. I think the speedo can be recalibrated at a dealership, but it's not worth the trouble. Plus I plan on getting bigger tires sometime and that will make it even more innacurate.

 

I'm not lost!

I just don't know where I am.

[Couch_Potato]

quote:

---

Originally posted by TheCacheCrew:

Don't know the official details, but...

 

The V registers 2.5 mph faster than the speedo on our Xterra. Stock tires and wheels.

---

 

Odd, my stock Xterra reads about 5% faster than the GPSr. Speedo reads 70 and Legend only shows 67.

 

I'v just assumed that the speedometer is calibrated slightly wrong. I think the speedo can be recalibrated at a dealership, but it's not worth the trouble. Plus I plan on getting bigger tires sometime and that will make it even more innacurate.

 

I'm not lost!

I just don't know where I am.

[+GOT GPS?]

All my GPS units seemed to read about 3 mph faster in the 86' Olds Cutlas Cierra and the 96' Escort Wagon, that i have(got rid of the previous one).

 

It is better if you drove the car using the GPS screen that shows both Speed and direction of travel. It is easy to get pulled over for speeding, the way the Vehicle speedos are calibrated. Like not driving 5mph over the speed limit according to your car's speedometer.

 

My home page about GPS units and information

[Us 5 Camp]

Search the archives on gps speed or speedometer accuracy.

 

I believe you'll find GPS speed indications are accurate to within tenths of a mile per hour.

 

I certainly trust the gps speed more than my auto speedometer. I've timed all my vehicles while on long road trips and my calculations of actual speed agree with the speed indicated by my gps.

[Movinfr8]

quote:

---

Originally posted by rwinters:

But I did change to lower profile tires so my speedometer could be off and the Garmin just made that evident.

---

 

check the difference at 25 mph, then at 70 mph. If it is tires (and I suspect it is) shouldnt the "error" be significantly greater at 70?

Norm

[NetDep]

Easy enough - just hop in a car with a friend who has radar with your Garmin V and you will soon have the answer. The Garmin V is *very* accurate - pretty understood that speedometers are off varying amounts (can take them to a shop and get them calibrated but normally no need to). The GPS was right on with the moving radar - kinda cool too. HAPPY CACHING!!!

[NetDep]

Easy enough - just hop in a car with a friend who has radar with your Garmin V and you will soon have the answer. The Garmin V is *very* accurate - pretty understood that speedometers are off varying amounts (can take them to a shop and get them calibrated but normally no need to). The GPS was right on with the moving radar - kinda cool too. HAPPY CACHING!!!

[+ApK]

My eMap has shown me that my Subaru's speedo is off by 2.5 mph and the odometer is off by 2.5%. My dealer says that is within acceptable limits. Kinda sux though that it will mean my warranty is over a thousand miles before it should be. I maylook into having it recalibrated. BTW, I checked the gps against highway milemarkers and the GPS is right on.