garmin traffic accuracy?

There's not a refresh interval option. Once it gets a signal, that's all there is. I think they transmit a "looping" transmission of traffic in a metro area, but I can't imagine it's a long delay in the loop end-to-end.

Likely it's a delay on their side of adding/removing traffic blockages to the signal they send. I usually suggest people take it with a grain of salt. Generally if it says there's a long delay, I believe it, but for a few minutes here and there, I find it's often times wrong. And then there are the "fresh accidents" of course that aren't reported but are major delays.

I have the msn receiver for my 885t. It's very accurate here in Chicago.

Remember the traffic is transmitted from third parties like Clear Channel's Total Traffic. The unit can only update as quickly as Total Traffic makes the update. In my case, it is rare that an update occurs outside of the weekday rush hours.

The Total Traffic website lists radio stations in the area as sources of the transmissions. I am betting that at least part of the process relies on people inputting the data into a computer to transmit.

I am very disappointment with the traffic receiver in my 755T, he only confirm that i am in traffic with delay when i am already on traffic, wonder what??, i am already know about the traffic. Miami area.

I have also noticed a lag in traffic info on my Garmin compared to Google Maps. I wonder if they get the info from the same location.

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I guess that doesn't work that way in all cases. The other day while traveling North of Baltimore I received a notice that there was a traffic problem 19 miles ahead. Plenty of advance time for me.

I usually get advanced notice, 'cept where I'm in the middle of traffic when I turn the unit on. I live close to the interstate.

Gary Hayman

The traffic reports in the DFW area seem to be delayed and are not very accurate. I'll get a traffic warning and as I approach the area it will be clear and then there's the cases were there is traffic and no indication is given on the Garmin. I had hopes that the pay systems were better but from the posts they seem to be all the same.

That's exactly the same that happens to me, so i don't trust the traffic reports anymore.

My 765 is great but the traffic rarely works here. It'll tell me there's traffic when I'm sailing along & nothing while I sit at a standstill, all while getting a green light on the receiver plug. Maybe someday...

I too am disappointed in my traffic receiver for my 850 (MSN Direct). With all this technology working for you I was surprised at the lameness of this feature. I invisioned a world were my Garmin/MSN Direct was my all-knowing co-pilot who, sensing a traffic jam up ahead, would suggest an alternate route to get me to my destination with minimum delay. Intead I get the obvious (Oooo, watch out, traffic ahead) as I sit idling in traffic jam. This gives me time to wonder why I'm paying for this valuable information??

Garmin/MSN needs to step up and create a real solution for avoiding traffic, not just telling us the obvious.

It looks like we are in the same position. I live South of Baltimore, close to the interstate. I usually get good information, in plenty of time. It has helped me to avoid traffic many times.

I have used internet sites (google, MSN, ABC affiliate, etc) and found BIG differences in timeliness and accuracy.

In SOCAL area, there are many AM /FM radio sources that give more accurate and timely traffic reports (ususally from motorists calling in). CALTRANS also has accurate data on their internet site and I think they get avg speed from those little wires imbedded in the freeway lanes...

Well, I was never happy with FM Traffic until I started hanging the power cord over the rearview mirror. What a difference. If only there was some way to connect an antenna outside the vehicle, reception would be much better. I get some Norfolk FM stations almost all the way to Richmond. But, I live just on the edge of getting a green light on my GTM-20 (less than 1/2 the range of the vehicle radio).

Although, one time on a trip to Baltimore, the Garmin was telling me about a 30 min. traffic delay on the beltway around D.C and I was at King's Dominion. Not bad for the jam being 80 miles away.

It really depends how fast the State Highway Departments (or the contractors) passes on the info. And if you can't get a good FM signal, you don't get the updates.

If you want "Real Time" traffic info, you should visit trafficland.com . They don't have camera feeds from everywhere, but they do have a lot of feeds from all over the world. They do have most of the feeds from U.S. states.

thanks for the replies. i think also that nuvi traffic feed might be different from those of garmin xt (mobile phone type). i wish there was a way to integrate some of the newer google traffic info-it now does not only highways, but also big streets as well. has anyone here used google mobile maps and compared that to garmin?

I have a 265wt. I have concluded that the traffic feature is worthless.

i just recently ended up making a huge detour b/c the garmin xt put too much weigh on traffic on interstate, while not considering the traffic on major non-interstate roads.

Having the traffic info only covering the major roads makes the assumption that alternate routes (with no data) are clear.

I have decided that I will not pay for my MSN service at the end of the trial based on this primary flaw.

If the system is going to redirect you it should know that the alternate route is actually better rather than just not having any data.

A few weeks ago my 780 detected a massive jam on the interstate and attempted at every opportunity to redirect me into downtown Seattle....where traffic was absolutely gridlocked.

Since the unit had no data about the alternate streets it assumed they had to be better than the interstate...

AM radio reports are vastly superior to MSN for me.

MSN is not much better

I have used the Navteq traffic, Clear Channel traffic and the MSN Traffic here in Tucson and at least in this area the MSN is far more comprehensive and timely than the two FM traffic options.

haha..the lesser of the evils. well, i hope this will get better soon. i think google already implements major non-highway roads.

I live in Houston and the accuracy of the traffic data is spotty at best on my 765. Sometimes it is vary accurate other times it is no where near correct. I assume this is related to the data service and nothing to do with the GPS itself. Most of the time I keep it turned off.

I am fortunate not to have to travel in traffic very much. I live north of Dallas, but I have noticed, a few times, that when it shows a delay, it won't be there when I get there. Then I have noticed that it is spot on at times, too. Good ol' technology. I like the MSN for it's other uses (Stocks, news, etc.)

You are correct, "spotty" performace (and timely upates) are an issue with the service rather than the GPS. It's true everywhere I've ever travelled. Sometimes good sometimes horrible, but certainly undependable and unpredictable.

to consult before leaving the house. Won't be of much use if your are on a lengthy drive (as traffic conditions can change rapidly as time goes by). But it gives a good idea which way to start out....

http://trafficland.com/

I use this daily to get a first look at the daily commute. It works well and has inputs from local traffic cameras so you can make your own determination.

I have reported this before... true that the 'severe traffic ahead' alert tries to reroute you off the interstate into terrible city streets (as noted, because it has no idea of the conditions on the secondary roads). However, while the reports appear to be highly accurate in the Phoenix and N California areas as far as location, the 'delay time' given has no basis in reality. A slight slowdown might show red with a 10 minute delay, while gridlock might show yellow with a 2 minute delay that turns out to be 15-30 minutes.

How can they attempt to reroute you based on these ridiculous delay estimates??? At the moment, I have my 765 programmed to avoid traffic, but I plan to eliminate that avoidance and rely on looking at the screen and decide where to get off myself. Too bad there is not an option to say ignore the reroute this time.

Also, regarding secondary streets, I have noted in the Phoenix/Glendale area, Bell Road (a major secondary street) has traffic info even though it is not a major highway. (I use MSN Direct.)

MSN traffic more accurate than other FM traffic. But XM traffic still the best.

Just turn off the auto-avoidance and it will work the way that you want. It will warn you of a traffic alert and you can decide if you want to avoid it it or not.

I found the exact same thing with my 760, using first the standard FM traffic receiver and then later switching to MSN. You just simply cannot blindly rely on the traffic info and rerouting. If it's rush hour and it says 10 minute delay because of slow traffic, traffic is going to be slow everywhere, so there's no point in avoiding. If I see that the delay is because of an accident or construction, I avoid it.

Much, if not all in many areas, of the content is from the state - it won't differ from provider to provider. But some area's are clearly more responsive, deep and robust.

Note also that many areas only Update during rush hour weekday's while others are 24/7, 365 days a year.

Another related discussion is found here: http://www.poi-factory.com/node/24889#comment-155734

I live in the DC area and have a Garmin 780 with MSN Direct. The coverage is excellent and has saved me several times in DC Metro plus when traveling in Pittsburgh, Scranton, and Harrisburg. I've come to blindly trust my Garmin when it reroutes me to an unexpected route as the few times I ignored it, I got stuck in traffic and lost up to an hour of time.

To be fair, when you first try the service, you will need to gain your own confidence in the system by trying it a few times and ignoring it a few times and comparing the results. I strongly recommend the service in my area.

My 765T was surprisingly accurate around Dallas last week. I was very suspicious that it routed me right downtown to get to DFW. It said that there would only be about 5 minutes of delay at 5PM. I thought it was crazy. However, after getting through the jams and getting to DFW only 2 minutes later than it said I would, I'm a believer. I'll be moving there in a few weeks, so we'll see if it can keep it's record going.