13' spec height - what is lowest tunnel or bridge you will go under?

[Stripe34]

Our upcoming 4018 DSDP has a spec height of 13'. I'm guessing that is approximate? Has anyone measured their actual height vs spec?

And - while driving - how many inches of labeled clearance is your cutoff? Will you drive your 13' rig through a 13'2" tunnel? 13'4"?

Lastly, for weight - do you just consider that you are approx GCWR (when towing) and plan your route over bridges accordingly? Or do you feel safe enough cutting it closer to actual weighed or calculated?

We need to get our trucker/RV GPS before the coach, methinks :-)

Thanks for your thoughts!

[MRUSA14]

I would want at least 6 inches more than my measured height. Don't forget that when they repave, the road gets higher but the bridge does not, so I take the bridge clearance markings with a grain of salt.

To measure your coach height, you need a straight 8 foot board (a 2X4 works well), a level, a tape measure, ladder and a helper. Park the coach on the most level ground you can find. Once on top of your roof, hold one end of the board on the top of the tallest object (usually an A/C or antenna) and level it with the level. Then have your helper measure the distance from the free end of the board to the ground. Do this on both sides of the coach and average the numbers and you have your coach height.

[Route 66]

I had measured my DSDP and I recall it was a few inches higher than the 12'3" spec at 12'6".

13' was my limit, but I never encountered a clearance problem.

I always traveled Interstate or state roads and clearance or weight was never an issue.

Local roads to campgrounds were always OK.

[Algoma]

When you get your RV GPS (I have the Rand McNally) you can plug in all your dimensions and then, theoretically, your routes will not have any restrictions. I do not use GCWR as my actual weight is at least 10,000 lbs below that. But even so you are unlikely to find that an issue. BTW, there are also speed restrictions on some hills based on vehicle weight so you may want to keep an eye out for that. And no you don't have to go through a weigh station if you are over the posted weight as that is strictly for commercial vehicles.

[Wryly Blithe]

Originally Posted by Algoma

When you get your RV GPS (I have the Rand McNally) you can plug in all your dimensions and then, theoretically, your routes will not have any restrictions. I do not use GCWR as my actual weight is at least 10,000 lbs below that. But even so you are unlikely to find that an issue. BTW, there are also speed restrictions on some hills based on vehicle weight so you may want to keep an eye out for that. And no you don't have to go through a weigh station if you are over the posted weight as that is strictly for commercial vehicles.

One problem with relying on your GPS for height restriction warnings is that they often don't warn you about arched tunnels.

There is a tunnel on hwy 50 outside of Lake Tahoe that's marked as 18' 6" in the center but the right-hand lane is only 12' 4" because of the arched opening. Many GPS's won't pick that up, so it pays to scout ahead using something like the Low Clearance Database or Mountain Directory.

[lucyh]

The person who mentioned repaving as changing bridge heights is absolutely right. A driver at our dealer told us a story about running into a bridge when delivering a park model even though the DMV had routed for him. Turns out they had repaved the road and didn't remeasure the height. So, I'll always choose to have at least 6" extra.
I use CoPilot (they have RV and truck versions) on my phone. You tell it the height, weight, etc of your vehicle. It's sometimes over-conservative on routing but I'd rather be safe than sorry if I don't know the roads.
If the campground is not on obviously major roads and doesn't give directions from a major road on its website, I always call and double check with the person at the campground to make sure there aren't approaches I should avoid.

[HavingABlast]

Originally Posted by MRUSA14

I would want at least 6 inches more than my measured height. Don't forget that when they repave, the road gets higher but the bridge does not, so I take the bridge clearance markings with a grain of salt.

To measure your coach height, you need a straight 8 foot board (a 2X4 works well), a level, a tape measure, ladder and a helper. Park the coach on the most level ground you can find. Once on top of your roof, hold one end of the board on the top of the tallest object (usually an A/C or antenna) and level it with the level. Then have your helper measure the distance from the free end of the board to the ground. Do this on both sides of the coach and average the numbers and you have your coach height.

In your case, your rig is a DP, you want to do this with the coach aired up, not with the air dumped out.

[Mainuh]

Originally Posted by Stripe34

Our upcoming 4018 DSDP has a spec height of 13'. I'm guessing that is approximate? Has anyone measured their actual height vs spec?

And - while driving - how many inches of labeled clearance is your cutoff? Will you drive your 13' rig through a 13'2" tunnel? 13'4"?

Lastly, for weight - do you just consider that you are approx GCWR (when towing) and plan your route over bridges accordingly? Or do you feel safe enough cutting it closer to actual weighed or calculated?

We need to get our trucker/RV GPS before the coach, methinks :-)

Thanks for your thoughts!

We just had our MADP weighed by the Escapees Smartweigh at the VT rally (individual wheels, not just axles). We were almost 2000 under on each of the 3 axles, but I did find after consulting the Michelin tables for my 315 tires, we're over inflated on almost all of them,*so making adjustments there. Maybe that'll soften the ride a little.

They also measured the coach with their measuring tool. We noted their tool's horizontal arm was less than 90 degrees so I think they were building in a small fudge factor, but our spec is 12'8" and they came up with 13'3" which is higher than we'd have guessed. They said the fantastic fan vent covers were highest but the satellite dome appears to be as high as them too or possibly higher. I ned to get up there with a board and level and double check soon! But for now I wouldn't think of anything less than 13'6" for an underpass.

[Crazeee1]

Originally Posted by Stripe34

Our upcoming 4018 DSDP has a spec height of 13'. I'm guessing that is approximate? Has anyone measured their actual height vs spec?

And - while driving - how many inches of labeled clearance is your cutoff? Will you drive your 13' rig through a 13'2" tunnel? 13'4"?

Lastly, for weight - do you just consider that you are approx GCWR (when towing) and plan your route over bridges accordingly? Or do you feel safe enough cutting it closer to actual weighed or calculated?

We need to get our trucker/RV GPS before the coach, methinks :-)

Thanks for your thoughts!

Most, not all, posted heights are posted with a smidgen of wiggle room. At least in Iowa. I took my semi under a bridge once that was posted 13'4, course I went real slow and dumped the bags just in case.Unless an emegency, I would not chance it. Any damage to underpass and you are liable. Weights, if close, I .....yes. If you get stopped and weighed on route, and trooper asked you where you come from.....well(that's another story).

[twojayhawks]

The other thing that hurts you in low clearance situations is an incline/decline. Many low clearance situations are going under a train crossing or a road. With a longer vehicle any change in level can also eat into your clearance. Isn't there a web site that shows videos of vehicles being damaged for lack of clearance. 11 FOOT 8 - The Canopener Bridge

[Gordon Dewald]

Excerpt from Interstate standards:
Vertical clearance: Minimum vertical clearance under overhead structures (including over the paved shoulders) of 16 feet (4.9 m) in rural areas and 14 feet (4.3 m) in urban areas, with allowance for extra layers of pavement. Through urban areas at least one routing should have 16-foot (4.9 m) clearances. Sign supports and pedestrian overpasses must be at least 17 feet (5.2 m) above the road, except on urban routes with lesser clearance, where they should be at least 1 foot (30 cm) higher than other objects

[Pexring]

Interesting thread. I got a measurement of 12' on my coach doing the eyeball method with the tape measure. So I give myself a foot of leeway. Not only for adding pavement, but if the coach would also hit a bump about then and bounce.

[britcon]

If you stick with major highways and roads ( truck routes ) you should be OK on both height and weights. Need to be cautious when leaving main roads to find an RV park or ?? a couple of miles off the hwy. Small bridges, culverts, etc. sometimes have weight restrictions.

[Jager]

How much do you believe the specs on the bridge or tunnel? What if they laid down another couple layers of asphalt since the sign was put up?