I drive a 3.67 m truck.

I would greatly prefer to stay under 3.2m. Tis seems to be the sweet spot for low bridges. Also towing services and roadside assistance seem to get more expensive.

Other sweet spots seem to be 2.80, 2.30-2.40, 2.10, 1.90m

We aimed for a maximum height of 3.5 metres , Which is exactly what we are.

We were slightly under, then had new leaf springs fitted.

We are 1950 mm inside the cabin and its more than enough.

It was a simple formula that got us to this size.

Garage tall enough to put a bike in + Bed base and Matress + wife sitting up in bed drinking tea = 1950 mm

Neil

Cloud 9 is Born

Our truck is 3.45 mtrs, slightly higher than the driver's cab. The living unit is almost 2 mtrs standing height inside which is comfortable enough for people shorter than me...
If you build something make it high enough to stand in. Don't worry too much about overall height as long as you don't get too close to 4 meters which is the minimum height for most bridges and tunnels in most of Europe.
IMHO fuel consumption is irrelevant for a truck this size, it won't matter much if you are 3.5 or 3.8 mtrs.
Most normal truck/trailers are about 3.8 mtrs so that should be a max guideline.

My camper is currently 3.83m with unmounted spares on roof. I'm trying to get them off, it will then be 3.53m including 10cm roof vent. With tires partially deflated with CTIS down to 33% highway pressure (takes just 3-4 minutes to deflate) it will get down to 3.48m, just below a 3.5m "cutoff". I'll still have one mounted and one unmounted spare on the back of the camper.

Charlie

Test.
 

With all this talk about height, I wonder where you are going.
If you are going to drive roads in developed countries, you can match the height of the largest delivery trucks and get through almost anywhere but, if you are thinking about going off sealed roads there are other factors to consider.
A lot of vehicles I have rescued off road are tall and the reason they have got into trouble is that the owners have been worried about tipping over when the track is around the side of a hill and they have driven somewhere else and come to grief. The other scenario is a steep road shoulder and they fall over into the roadside drain. Go somewhere where earth roads get wet and soft and one side sinks and you can end up with the truck lying down.


If you are thinking about going anywhere where the roads are earth there is a very good possibility that you will encounter a sloping road or very deep ruts. If you want peace of mind, test your loaded vehicle by setting up some big restraints over the top of the box and jack or lift with a fork lift to the balancing point and make a small pendulum inclinometer for the cab so you can see if you are safe when driving in these places.


Al.

Great info here, thanks.

My RB44 is 2.7m high and 2.13m wide. I couldn't get through several villages in the mountains of northern Portugal because of these dimensions so I wouldn't want to go any bigger. The big downside is that it is only about 1.7m in the back!!

Where I’m going?
On the unmade road to Cape York in Queensland, not exactly an unusual destination, I had to use a long handled tree pruning saw. In Strasbourg I couldn’t get into a campground through the front because there’s a ~3.7m bridge and at that time I had unmounted spares on the roof. I had to use the back service entry. And there’s that 3.5m bridge in a village to get under to access Lake Baikal beach....
Now tires on the back and down to 3.55m. Can get to 3.49 with CTIS deflation.
Obviously the 3.5m “barrier” still a close squeeze; but what can one expect with a 12.5 ton truck with 395 tires?

And with no tires on the roof, the heaviest things are solar panels. The COG is little affected whether the top is 3.7 or 3.3; the plastic panels are virtually weightless. Tipover angle is easily calculated with a few measurements and simple formulas involving only trigonometry.
Mine increased from 29 to 31 degrees by decreasing the wheel offset with Hutchinson wheels. My track width is about 1.97m. The sine of 30 deg is 0.5. Believe me, one gets very apprehensive when one side is even much less than 1m lower than the other.