The Ins and Outs of RV Height and GPS Navigation

Avoiding Low Clearances and Staying on the Open Road

So there you are, the kids are strapped in, snacks are packed, and you’ve finally bid the rat race adieu. But just as you’re settling into the driving groove, you round a bend and – clunk! – your air conditioning unit smacks into a low bridge. Not exactly the carefree start you’d envisioned!

Situations like this are more common than you’d think for RV newbies.

Measuring Up: Determining Your RV’s Height

The first step is figuring out exactly how tall your RV is. This sounds simple, but can get tricky if you have add-ons like air conditioners or satellite dishes on the roof. You’ll need to measure from the ground to the absolute highest point on your rig. A retractable tape measure or yardstick works fine, but you may need a step ladder to reach the roof.

When measuring, be sure to account for factors that could increase your RV’s effective height on the road:

  • Roof vent fans or antennas raised
  • A/C units
  • Raised satellite dishes
  • Anything else mounted on the roof

And don’t forget – measure from level ground while the RV is unhitched, fully loaded and ready to roll. Those few extra inches when packed with gear or hitched to your tow vehicle can make all the difference!

Once you have your maximum height in inches or feet and inches, write it down somewhere handy like on a dashboard sticker. Trust me, you’ll need it again.

Programming Your GPS With RV Height

Now comes the fun part – telling your GPS just how massive your home on wheels is! Most newer GPS units allow you to input vehicle height and avoid low clearances. Here’s a quick walkthrough:

Onboard Vehicle GPS
  • Tap or scroll to the settings menu
  • Look for an option like “vehicle height”, “clearance height” or “avoid low clearance”
  • Enter your RV’s height measurement in feet and inches or inches only, depending on the unit
  • Save changes

That’s it – your onboard GPS will now route you around any low clearances and tunnels based on the height you entered. Keep in mind, the factory default is usually around 12 feet, so be sure to change this.

GPS Apps

Popular GPS apps like Google Maps, Waze and Apple Maps also let you set vehicle height. This functions the same as onboard systems:

  • Open the app settings menu
  • Look for “Vehicle Height” or “Avoid Low Clearances”
  • Enter your RV height and save

One advantage of apps vs onboard GPS is that your height preference stays synced across devices. But double check this each time you switch vehicles or apps.

GPS Devices

For handheld GPS devices, you’ll need to consult the manual for specific model instructions. But the overall process is similar:

  • Access system settings
  • Find and enter your RV height
  • Save settings

Garmin and TomTom both have this capability on newer models. Again, be absolutely sure your changes are saved before heading out. Nothing like learning this lesson the hard way!

Let Your GPS Be Your Guide

Once you’ve got your RV height dialed in, your GPS can automatically route you around low bridges, tunnels and tricky spots. Pay attention to height warnings just in case, but in general you can rely on those trusty directions.

One thing to keep in mind is that many GPS units use 12 feet as the default height. So even if you enter your actual RV height, watch for low clearance warnings under 12 feet just to be safe. And ALWAYS double check the clearance posted on bridges and tunnels before proceeding. Don’t rely 100% on technology alone.

Watch Those Tow Vehicle Clearances!

Got your RV settings squared away? Don’t forget your tow vehicle! Even if you have a beefy lifted pickup, measure its height including any antennas, luggage racks or lights. And be sure to enter that height in your tow vehicle GPS as well. Nothing worse than cruising along only to smack the pickup nose into an underpass. Yes, I’m speaking from experience here!

Avoiding Other Road Hazards

While we’re on the topic of GPS navigation, most units also allow you to select preferences that steer you clear of other RV hassles:

Narrow roads: Check this and your route will skip streets and alleyways too skinny for your wide-bodied Winnebago.

**Unpaved roads: Dodge those dirt and gravel lanes that just kick up rocks into your exterior paint job.

Steep grades: Skip hilly streets that might overtax your transmission or send unsecured cargo sliding.

Toll roads: Save yourself the headache of stopping repeatedly at toll booths.

Toggling these on makes trip planning a breeze. Now if only GPS could reroute me away from ugly in-law relatives! A man can dream.

Updating Your Maps

All the high-tech routing in the world won’t help if you’re working from outdated maps. Over time new roads are added, clearances change, bridges are built. So make sure to routinely update your GPS maps and software to get the latest intel.

Most onboard auto GPS systems require taking your vehicle to the dealer for updates. For GPS apps and devices, check for updates in the software itself or periodically replace maps to stay current. Out-of-date maps can quickly negate the benefit of height and road preferences, so update regularly.

Back It Up With Route Planning

While GPS is invaluable, make sure you’re still doing your own route planning as a backup. Get out the maps and highlight routes between stops. Call ahead to verify bridge and tunnel clearances if you’re unsure. GPS and technology help minimize headaches, but your own careful planning is still key.

If I’ve learned anything from past navigation mishaps, it’s to have a solid route plan before punching the pedal. Otherwise you’ll be making some unplanned detours like my memorable day spent wedged under an Atlanta freeway overpass! But with some care and preparation, you’ll be smooth sailing in your land yacht.

Watching Your Top In Tricky Territory

Certain areas pose particular challenges for the height-conscious RVer. Mountains, historic urban centers, winding coastal roads – you’ll want to take extra precautions navigating routes like these. Here are some tips to keep from scraping the sky when route-finding through challenging terrain:

Winding Mountain Roads

Rocky mountain roads undoubtedly make for scenic cruising. But all that beautiful scenery comes with tight switchback turns and rolling elevation changes. Even well-maintained highways can hide hazards around blind corners. So take things slowly, watch clearance signs closely and brake early when coming downhill. Don’t let a steep downgrade carries you into an ugly underpass surprise!

Coastal and Canyon Roads

Similar vigilance is needed navigating ocean-hugging lanes and canyon pass throughs. Shoulder room is limited on the edge of cliffs and rock faces. And sea winds can really do a number on your gas mileage! If at all possible, opt for flatter inland routes or wider causeways. Just be ready to pay those hefty coastal tolls.

Urban Centers

Downtown districts definitely have their big city appeal. But they can be rife with low bridge underpasses from bygone eras. If you really want that urban sightseeing experience, do your underpass homework ahead of time using satellite view on Google Maps. Look for lights, piping or other telltale signs of low overhead passes and then plan your route accordingly. And by all means, avoid parking garages! Just take my word for it…

Leaf Peeping Season

If New England foliage tours are on your fall schedule, be extra vigilant during peak leaf peeping times. Historical rural routes get congested quickly with traffic jams at every covered bridge and scenic outlook. Avoid the worst bottlenecks by scheduling stops on weekdays if possible. And never trust an overloaded car’s ability to judge tunnel clearance ahead of you!

Construction Zones

While road construction can crop up anywhere unexpectedly, some areas see more consistent work. The Pennsylvania and New Jersey turnpikes are perpetual construction zones. So too are winding mountain roads out west. Adjust lane position frequently to avoid hazards like dangling light poles or signs. And don’t rely 100% on online maps or GPS in rapidly changing work areas. Trust your eyes and judgment first.

Bumpy Detours

Speaking of construction, be prepared for sudden detours onto makeshift side lanes and gravel access roads with exaggerated bumps and dips. You may have no choice but to brave these temporarily rerouted rough patches. Take it slow, dodge hazards and cringe your way through. Just keep those survival snacks and beverages handy for afterward!

Leveraging Helpful Hardware and Accessories

Alright, you’ve got your GPS dialed in and are avoiding low points like a pro. But a few other gizmos can make height management even easier. Here are some RV tools and accessories I’ve picked up over the years that really took the headache out of overhead hazards:

Roof Safety Flags

Fluttering banners mounted on long flexible poles are a dead giveaway that an oversized vehicle is coming through. Attach safety flags at the highest point on your RV roof to provide a visual low clearance alert. These draw early attention from construction crews and other motorists so they can clear the path.

Clearance Light Bars

Take roof flags up a notch with full rooftop clearance light bars. Their rows of amber LEDs really grabs attention and says “Look out! Winnebago coming through!” Helpful day or night. Just ensure any add-ons are included in your RV’s height measurement.

Hood Mirrors

Aftermarket hood mirrors extend your rear and side vision dramatically. These keep you aware of roof edges and toll booth overheads without straining your neck backwards. They take some getting used to visually, but are handy additions. Plus you can finally see who’s tailgating you!

Backup Cameras/Sensors

Don’t rely solely on mirrors! Add backup cameras at the rear roofline to see precisely how much clearance you have behind you. Audible proximity sensors also help warn you when things overhead are just a little too close for comfort.

CB Radio

The old school trucker CB may seem outdated, but it’s still invaluable for real-time road condition updates. Trucker tip calls of “low bridge ahead!” or “construction, single lane” can alert you to sudden hazards before it’s too late to reroute. Keep that CB mic handy!

Minding Road Conditions Near and Far

We’ve covered navigation tricks, gadgets and planning. But it’s equally important to pay attention to the actual road conditions around you. Potholes, erosion, weather impacts, and other factors can change clearances in an instant. So stay alert on the go and think ahead.

Watch for Sagging Signs and Trees

Keep an eagle eye out for low-hanging traffic signs, tree limbs, or wires drooping over the highway. Storm damage or aging infrastructure mean these items sometimes encroach lower than their installation height. Give them plenty of clearance just in case.

Beware of Low Shoulders

Paved road shoulders can erode over time, reducing clearance and exposing rough gravel edges. Hug the main lane to avoid surprises. And absolutely stay off soggy verges after heavy rain or thaws. It’s all fun and games until you’re mired axle-deep in mud!

Slow for Potholes

Major potholes and pavement divots throw off your clearance height, especially if they’re on inclines or declines. Hitting them head-on also wreaks havoc on your suspension. Scale back speed on uneven surfaces so you can swerve and brake for pits and potholes.

Allow for Ground Clearance

That 24-inch ground clearance means something – let those wheels do their job! Where possible, straddle or drive around low points rather than bottoming out your rig. And take speed bumps, railroad tracks and steep driveway aprons at an angle to avoid underbody scrapes.

Factor in Weather Impacts

Finally, remember weather that tosses around your RV can also wreak havoc on roads. Heavy snow can significantly lower underpasses until plows finish their work. Watch for flooding in low-clearance tunnels or bridges during downpours. And allow ample stopping space in case crosswinds throw you off course. Planning your route means planning for anything Mother Nature might throw your way!

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