To Bill and all that have added to this thread:
Thanks for all the comments. I too have been a happy Garmin user. And I've seen lots of good reviews on the RV760LMT. However, then I run into reviews like this:
"I've always been a Garmin fan and was thrilled to discover that Garmin had developed an RV specific GPS. I purchased the Garmin RV 760LMT and tried it out on local streets while driving my car. All went well.
About a week ago we embarked on our annual winter trek with our 41' motorhome and towed vehicle.
So far... EPIC FAIL!
First off, the unit doesn't have an option to enter our RV's propane capacities. So it will route us into restricted tunnels.
Of the eight locations we've entered into the GPS, the RV 760 has correctly led us to two!
We entered a truck stop that unit suggested. We followed the direction off the interstate and immediately got that sinking feeling that we would not find a truck stop in this residential neighborhood. Then the unit pinged and advised us that we would be 'navigating off-road' for 1.2 miles! In a 41' motorhome! When we got close to our 'truck stop' we found ourselves looking at a funeral home.
Another recommended truck stop turned out to be a convenience stop with fuel pumps. This one was impossible to access with our rig. And yes, the unit is in RV mode with all the correct parameters correctly entered.
It's disconcerting to be driving along the recommended route and get a message that says, 'Unknown if current route is suitable for your RV'. Oh my freaking Lord, I bought this thing to keep me on routes suitable for my RV!
Today the camel's back shattered. I entered tomorrow's destination into the unit. When I reviewed the route, I lost it! Had we followed the recommended route we would have driven down a long, narrow, winding road, down a steep hill to a ferry. This ferry has a 5 ton limit! I know this because we just happened to go out for a drive today and happened to be on that particular road. Our rig weighs 17 tons. And there would have been no place to turn around had we ended up down there.
It's got some nifty features. But it fails do perform the most basic features that I require in an RV dedicated GPS. That is, keep me on roads that I can travel safely, and legally.
Garmin has a lot of work to do before they can market a reliable GPS for big rigs. Buy something else or wait until Garmin works out the countless bugs in this unit."
AND THIS:
"Warning, this is about the most inaccurate gps I have ever dealt with. As a standard navigation gps I suppose it's ok, but when you are using it in RV mode that is when its issues crop up. It seems unless you are within a few miles of major highways the RV function is useless. It will display "RV accessibility unknown" on a good 50% of the smaller roads in my area (western PA). The other info it gives you such as "sharp curve ahead" or "steep hill ahead" is also essentially useless, as it does not tell you how steep or how sharp. From what I can tell it makes no difference in the route it gives you if you input your rig as 28' or 58'. The first time I used it I programmed an Army Corps campground in Vermont as a destination. Even though the gps lists the campground and its amenities it directed me to the Corps main office 7 miles away from the campground. It also sent me to a PA state park office instead of the campground on the same trip. Garmin apparently did not do enough research on the maps for this, some major RV parks, State and local parks with campgrounds, and private campgrounds are not even in its database. Save your money. use a standard gps or a map. I am beyond the Amazon 30 day policy so I am stuck with this $400 toy, you need not be."
AND THIS:
"This unit is advertised as a product that is designed to support the RV owner. As a full-timer I rely heavily on a GPS to not only give me directions to where I want to go but also give me information on camping sites and RV parks. This is the task that Garmin fails miserably at. You would think a $500 GPS, with Garmin's name on it, it would work well; what a disappointment. The database of know parks is not accurate and the search function is finicky and is grossly in-accurate. I already have a Rand McNally GPS made exclusively for RVs and it works well thanks in part to using Good Sams and and Goodalls databases of know and well documented Federal, State and local RV parks. It is amazing the difference in the two products but I was really supprised how badly this Garmin device performed. Garmin, at least to me, has always made the best GPS available, but somehow this product fell through the cracks. Evidently whoever at Garmin developed this product never went camping."
OUCH! These 3 reviews are from Amazon.com. Sure, there are more good reviews than bad but that makes me nervous too. It gives me the impression that they work well until they don't (goes for any GPS). And when they don't...be prepared to unhook your toad and back up for a mile or 2 to get out of a sticky situation...assuming it wasn't a lower than advertised overpass that just removed your mobile satellite TV antenna...or worse. Even the CoPilot Truck app for Android/IOS operating systems doesn't cover "noncommercial" truck routes...which means if you're on a Eastern US parkway that doesn't allow commercial traffic, it won't protect you.
I know there's no perfect device. Even if there was, the databases they work from are subject to error....that 13'6" database clearance is really only 11'6". When I lived in Maryland I had a fly-bridge cabin cruiser that when is was trailered, the radar dome was 13'8" off the pavement. I didn't trailer it anywhere I hadn't already scouted in my pickup. I prefer not to do that in the Beav. I also don't want to stick to the interstates, which always represent the safest routes.
I still want to hear from others, My 6 year old Garmin 520 Street Pilot is about 98% accurate. However, last year it lead me to a ferry crossing even though I had it on the "Truck" setting. Fortunately I was in the Jeep...no biggie. In the Beav...a lot of extra miles would have been burned finding another Class A certified crossing.