Juddian:
As above, go old school a bit (common sense, plan route by bridge height map) and new tech a bit, let a common or garden satnav help you with looking for turnings and which road to take from an unsigned roundabout say.Last time i used the fitted satnav was to a place out in the wilds of the fens, instead of following my own above advice i simply punched in the postcode and let it lead me from about 5 miles out.
Boy oh boy, it took me down single track twisting blind lanes with typical fen ditches either side, had i met another lorry we’d have had a serious problem, lots of lorries go this way no doubt following satnav cos the corners were all scrubbed down due to tyre wear.Whilst tipping i got me trusty map out, and realised by travelling some 1 mile further i simply had to turn right out of the yard, travel about 2 miles on a decent B road to a cross roads, then turn left along an equally straightish fen road back to the main road, easy peasy.
You do not need a lorry sprecific satnav, you need a decent bridge height map, i prefer AA truckers atlas which is clearer to read than Philips, and a reasoanable satnav or google maps on your phone, google maps is brilliant for the live traffic, but Garmins Digi Traffic (must be digitraffic) runs it a close second place, plus you can let the satnav run 24/7 at no cost in data.
Satnavs are brilliant pocket sized street maps of the country, and a good way of confirming you are on the right road, good for spotting unmarked turnings in the dark, speed limits, camera sites etc.A pro lorry driver should never allow a satnav to plan their route, that is your job via a map because it’s you not the bloody 'puter who is in charge of and responsible for the wagon, by all means program a reasonably priced satnav and confirm its looking at the same route and let it assit you along the way, for that purpose they are brilliant devices, but do not put your trust the bloody thing.
My sat nav did something similar, tried (and I say tried because one look at the road and there was no ■■■■■■ way I’m taking a lorry down there) to take me down inappropriate roads. I changed the route preference from “shortest route” to “fastest route”. It seems to keep me on bigger roads for as long as possible, pretty much what I plan on the atlas really.