There is no right answer.

   My  Garmin Sat Nav receivers display navigational accuracy between 7
feet and infinity (lost in the woods) I can put two of them side by each on
the dash, the 2004 model says I'm within 7 feet, but a 2008 model with a
much more sensitive chip is always at least double that.

Geo/ATL

On Wed, May 8, 2013 at 10:08 AM, Todd Last <rubatoguy@comcast.net> wrote:

> Thought I would share this response from Garmin about the speed accuracy
> of their unit.
> Don't you just love tech support that never answers your question.
> Probably reading from a script approved by the company lawyers.
>
> Todd
> '88 Westy
>
> ----- Forwarded Message -----
> From: "Product.Support@garmin.com" <product.support@garmin.com>
> To: "Rubatoguy" <rubatoguy@comcast.net>
> Sent: Wednesday, May 8, 2013 5:23:51 AM
> Subject: Re: speed accuracy (KMM28238403I15977L0KM)
>
>
>
> Dear Todd Last,
>
>
>
> Thank you for contacting Garmin International.
>
>
>
>
> The speedometer on your device may display a different speed than the
> speedometer in your vehicle.
>
>
>
> The speedometer in a vehicle is based on calculations using tire rotation.
> On the other hand, GPS devices calculate speed based on your GPS position.
> The accuracy of the speed displayed on the vehicle and GPS device can vary
> depending upon whether the vehicle's speedometer needs to be calibrated
> and/or how accurate your GPS reception is.
>
>
>
> Please note that GPS devices should be used as a navigational aid and not
> relied upon for precise measurement of speed.
>
>
> Should you have further questions please contact Garmin Product Support by
> replying to this email or contact our Consumer Support Line at
> 800-800-1020 Monday-Thursday 8am-6:55 pm and Fridays 8am-5pm CST.
>
>
>
>
>
>
> With Best Regards,
>
>
>
> Russell B
>
> Product Support Specialist
>
> Automotive Team
>
> Garmin International
>
> 913-397-8200
>
> 800-800-1020
>
> 913-440-8280 (fax) Att: Russell B, Associate #5795
>
> www.garmin.com
>
>
>
> Additional solutions may be found at
> http://www.garmin.com/garmin/cms/site/us/support/searchsupport
> Original Message Follows: ------------------------
>
>         Escalation from KANA On Demand Self Service
> Subject: speed accuracy
> Message: What is the published accuracy of the speed measurement of this
> unit? e.g. accurate to or - 10% at 60 mph... or whatever. thank you
>         Knowledge Session Log URL:
> http://iqc.garmin.com/eCustomer/KODSelfService/sample.jsp?session=
>         Knowledgebase:  garmin
>         Market Name:    null
>         Product Group:  null
>         Product:        nuvi 3590LMT
>         Serial Number:  2H8061057
>         Software Version:
>         Type:
>         User ID:        rubatoguy
>         Name:   Todd Last
>         First Name:     Todd
>         Last Name:      Last
>         Email Address:  rubatoguy@comcast.net
>         Phone:
>         Address:
>         City:
>         State:
>         Zip:
>         Country:        United States
>
>
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