Garmin Question

[Boris7]

Mine insists on showing a lower speed limit for my 3.5T van as required for 7.5T vans but only on some roads. For example 50 in a 60 limit.
Some height limits which Garmin avoids may only apply over half the road width like at the sides of arched bridges, or where rocks overhang a short section of only one side of the road.

But for example on an A road the speed limit for a 3.5t vehicle IS 50mph just like the 7.5t van

 

[bartman]

But for example on an A road the speed limit for a 3.5t vehicle IS 50mph just like the 7.5t van

You're quite right, the relevant weight is 3.05 tonnes.
However I have to agree with Barge 1914 that the Garmin gives incorrect speed limits. On my Garmin Camper 770 it has always annoyed me that once you select "Motorhome" it lets you enter the dimensions including weight, but whatever weight you enter it assumes you are driving a behemoth. Perhaps its the US origins that are to blame, assuming that a motorhome is always going to have the dimensions of an RV.
I have the weight correctly entered as 2.8 tonnes, but the speed limits shown are 50mph on single carriageways, 60 mph on dual carriageways and 70 mph on motorways. No amount of tweaking the setup changes this. It is an infuriating fault on what is a rather expensive satnav, however I live in hope that they will fix the issue in one of their software updates........

 

[TJBi]

You're quite right, the relevant weight is 3.05 tonnes.
However I have to agree with Barge 1914 that the Garmin gives incorrect speed limits. On my Garmin Camper 770 it has always annoyed me that once you select "Motorhome" it lets you enter the dimensions including weight, but whatever weight you enter it assumes you are driving a behemoth. Perhaps its the US origins that are to blame, assuming that a motorhome is always going to have the dimensions of an RV.
I have the weight correctly entered as 2.8 tonnes, but the speed limits shown are 50mph on single carriageways, 60 mph on dual carriageways and 70 mph on motorways. No amount of tweaking the setup changes this. It is an infuriating fault on what is a rather expensive satnav, however I live in hope that they will fix the issue in one of their software updates........

Have you taken this up with Garmin Support UK? 0808 238 0000

 

[bartman]

Have you taken this up with Garmin Support UK? 0808 238 0000

They already know about the issue, but not interested in fixing it. I suppose in reality an expensive unit like that is more likely to be in an A class anyway

 

[Henrym]

Never found a need for it but my TomTom app allows you to input vehicle type and dimensions.

Fundmental question is, if you put the information in, what does it do with it? As other posts show, either nothing or goes over the top. Fundamentally depending on (a) how good is the source data from agencies specifying restrictions on road segments used by GPS and (b) how much effort SatNav providers will put into applying the data, with different rules in each country. Hence I now use the 'car' option on my Garmin Camper 660 and read road signs unless it's a particularly complex area. e.g. in Motorhome mode it will only avoid narrow roads IF there is a signed width restriction, usually to deter anything wider than a delivery van. But other narrow roads can still be permitted for wide vehicles, so it can be fun meeting a tractor with attachments (though their drivers are usually adept at getting into the hedgerow)!

 

[Boris7]

Fundmental question is, if you put the information in, what does it do with it? As other posts show, either nothing or goes over the top. Fundamentally depending on (a) how good is the source data from agencies specifying restrictions on road segments used by GPS and (b) how much effort SatNav providers will put into applying the data, with different rules in each country. Hence I now use the 'car' option on my Garmin Camper 660 and read road signs unless it's a particularly complex area. e.g. in Motorhome mode it will only avoid narrow roads IF there is a signed width restriction, usually to deter anything wider than a delivery van. But other narrow roads can still be permitted for wide vehicles, so it can be fun meeting a tractor with attachments (though their drivers are usually adept at getting into the hedgerow)!

Simple fact is I have no idea, my career (until very recently) was spent mainly on the road in various vehicles from Vans to Artics, back in the day (old git alert) we used to get to a back street in Casablanca, Sofia, Madrid etc with a 40ft trailer without a satellite to help out, therefore I don’t rely on tomtom too much.

If I’m going somewhere new I tend to look it up on google then simply either commit the last leg from the motorway exit to mind or if it’s complicated sketch out a stalks plan on paper and stick it on the dash.

The best thing with Sat Nav for me is I no longer have loads of street maps clogging up the cab and if traffic demands a detour I have a live map on the dash.

 

[philstoke]

I have had a Garmin Camper Satnav for a few years and is is useless at giving warnings for height or width restrictions, I have beed directed down roads with width or height restrictions loads of times.
I have even put my motorhomes dimensions a lot larger than they actully are but it makes no difference
None of the different satnavs I have tried can even keep you on A ot B roads instead of taking you down narrow country lanes, even though the actual mapping knows if the road is A or B rated

 

[jacquigem]

Pretty sure I was told somewhere (don't remember where)that Garmin relies on Google maps which do not hold road width information on a general basis. Hence they are pretty useless at stopping you going down narrow roads.
Once in the Pyranees we ended up on a narrow stretch and found a Google mapping van coming the other way. It's driver frantically waving his hands telling us not to proceed despite Garmin saying it was OK.
Driver beware I think.

 

[DTF]

Garmin do make use of Openstreetmap (OSM) data. In theory you could add width data for all road segments in OSM (anyone can update/add data) but it would be a massive task and some how you would need to actually measure the road width. What data is in OSM will most likely have come from people directly surveying road signs.

 

[sydnsue]

You're quite right, the relevant weight is 3.05 tonnes.
However I have to agree with Barge 1914 that the Garmin gives incorrect speed limits. On my Garmin Camper 770 it has always annoyed me that once you select "Motorhome" it lets you enter the dimensions including weight, but whatever weight you enter it assumes you are driving a behemoth. Perhaps its the US origins that are to blame, assuming that a motorhome is always going to have the dimensions of an RV.
I have the weight correctly entered as 2.8 tonnes, but the speed limits shown are 50mph on single carriageways, 60 mph on dual carriageways and 70 mph on motorways. No amount of tweaking the setup changes this. It is an infuriating fault on what is a rather expensive satnav, however I live in hope that they will fix the issue in one of their software updates........

A fix is unlikely. I have the latest 795 and it still gives the incorrect speed limits. I was about to try playing with the settings but after reading all your comments, I won't bother.

 

[Rumour]

Not all roads in the world or any given country are measured for mapping. All sat-navs have this problem, depending on which map they use as to which roads are wrongly or not classified. Also, designations in other European countries are different. We have been on lower classification roads in France, that are wider and better that A roads in the UK. And as far as I can find, classification is not about road size. It is about road usage. Yes, more traffic does normally mean bigger roads, but not always.

 

[paulhelenwilko]

We use co-pilot. You can have several different vehicle profiles and their dimensions.
I am not convinced it takes this info into account, maybe low bridges but not narrow lanes.

I think deleted member is correct the maps are generic and do not necessarily contain width data.

 

[TJBi]

We use co-pilot. You can have several different vehicle profiles and their dimensions.
I am not convinced it takes this info into account, maybe low bridges but not narrow lanes.

I think deleted member is correct the maps are generic and do not necessarily contain width data.

Yes, satellite navigation depends on the data available and its interpretation. Regarding widths, it is generally based upon official width restrictions reported to the mapping companies. The same is true in respect of heights: official height restrictions (low bridges, etc. ) and not low branches on country lanes. Width and height can vary with vegetation and whether or not it is trimmed!

 

[DTF]

The lane hedges only get cut twice a year around us and some are best avoided in vans this time of year if you are concerned about your paintwork. It is one of the reasons I have a DIY campervan.

The comment on road classification is an interesting one as one of my hobbies is contributing to Openstreetmap. Openstreetmap is actually just a very large database containing data that can be used to render (produce) a map.

There are basically only three type of data in Openstreetmap. Points, ways ( a series of linked points) and areas ( a closed way). A road is a way and defined by the tags given to it. “highway=unclassified” for example. Because Openstreetmap originated in the UK the tagging system for highways is based on the UK descriptions. It has been quite a challenge to get every country in the word to adapt this to their local descriptions. You can add the “width=?” tag to any or all parts of the way representing the highway.

I should imagine that most other sources of map data are probably using a similar approach to Openstreetmap.

It’s up to the data users (app developers) as to how they present or use the data and how they configure any routing software to take account of width restrictions for example. They may also use more than one source of data. Openstreetmap being “free” and others likely to have a cost to them.

 

[GWAYGWAY]

The Garmin Camper sat NAVs do let you enter vehicle dimensions. Basically the LMT range either 760, 770 or 780 for example.

It still occasionally routes us down some lanes that I clearly would not consider going down (famously around Symonds Yat!) so either I have used the wrong settings or Garmin believe my motorhome shrinks in the British weather.

As always with sat NAVs use a bit of common sense and don’t always turn right or left.

Been stuck there I met a belligerent Bolshie transit pick up driver that would fill me in if I,didn’t back all the way to a passing place.

 

[GWAYGWAY]

Garmin Questions do they let you put vehicle dimensions in ? Not necessarily the lorry or motorhome one !
Thank you

I have a size changeable one, I hate it so much I took it out and stuck it in a drawer and went back to my Tom-Tom original. Anyone want to buy it?