Demountable camper group

I mentioned this in the introductions page, so I thought it's about time I passed on the story of how we manage to break our truck.

With hindsight being a wonderful thing , this was completely preventable.

We had a Navarra D22 and S Karosser EC6.
We had a wonderful 2 weeks Island hopping in the Outer Hebrides, starting at Barra and moved north through South Uits, North Uist, Harris then Lewis. Every night parked next to a beach, bbq's on the rocks etc. but that's another story.

Anyway, the roads here were quite rough and nearing the end of this trip one of the air suspension bags failed.
Clearly we couldn't travel with just one airbag inflated, so we completed our journey from Lewis to Swindon deflated driving very carefully to avoid bumps etc. as best we could.

A month or so later we thought we'd just have a day out, not go very far, but take the camper, for the convenience of the loo and fridge etc.
It was quite early in the morning, on the driveway up to Donnington Castle, in the dappled shade was a speed bump that was not seen, it was also quite big. The bump up was OK, but the bump down was the problem. I can't describe the sound of the chassis cracking, but I knew something had happened. It wasn't until we parked and got out we could see the result. One truck with snapped chassis. Not a good day out.
Luckily the AA managed to get it onto one of their relay truck and took us home.

Lessons learned
Check your payload.
With hindsight, we were grossly overloaded for the Hebrides trip, as the facilities there were few and far between we carried too much stuff. Our current truck is a Ford Ranger, the very first thing we did once we had the camper on was visit a weigh bridge with the camper empty of holiday bits and pieces, but with my Wife and I, plus the dog. I can remember the specific number, but we were approx. 150Kg off the max permissible weight. So that's not a lot to play with when you start filling water tanks, carry tables, chairs, awnings, beer, wine, etc....

Don't delay with repairs.
We didn't get around to fixing the airbags, this actually failed because at some time, probably during a service, one of the mounting brackets for the handbrake got moved and was rubbing on one of the airbag bellows, this overtime rubbed a hole.

Don't ignore chassis creaks.
For some time the vehicle "creaked" as we travelled.
The insurance inspector identified, that there was a small crack in the chassis that was there probably for some time as it had rusted. But this was the weak point that eventually failed.

Don't get into the mind set that your truck is indestructible.
After 5 or so years with the Navarra and the camper, getting us up mountains, onto beaches, camping in Scotland in January at minus 15 centigrade and remained warm and toasty , we just got a little blasé and did not think what we might be doing to the truck.

Don't insure with the Caravan Club
Insert expletive here - nuff said

Sorry - I have rambled on for ages here.
I'll add some photos later

Wow thats the first time I've actually known some have this happen, saw the one picture on the net of an (Australian?) but then thats either outback/jungle tracks.


Have to say our Navara seemingly flexed a little but never to that degree.
bit of a combination of problems there that could happen to anyone, coincidental actually because Peaky' here had a problem after travelling in same area
although his damage on a later model Navara was restricted to the load bed floor as the same camper was trying to rip its cargo hooks clean out.

out of interest, where on the chassis rail was the original fault?

many of us here insure via Campton (link in the FAQ thread)

Z

Good call to check and check again. I outlined in an earlier thread that demountables put unusual stresses on trucks. Its to do with lateral and vertical loads not normally associated with a standard pickup carrying 'goods'

Cracks and breaks often begin their lives when the camper 'snatches' at the mounting points when not strapped down tightly. These snatch loads often exceed those exerted by the camper in normal use. I had an issue with a load eye pulling through the buck floor. Once it had moved up 10mm it allowed 10mm of snatch, and that was enough to cause other problems. An afternoon in a fabrication shop cured everything for around £100.

it's also well worth putting your truck on a weighbridge to get a good idea of available load carrying capacity.

The demountable mantra really is :- if you don't need it don't take it and buy a lighter version of anything you can.

Have to say I actively look around for things to leave out these days, although I really should get it weighed empty as then its relatively easy to weigh things and add them,
I don't carry a lot of water generally as thats an issue, but stop short of carrying refilling hose

I always worried about this with my L200 with the Apollo.

At rest there was about a 30mm gap between the bottom of the overcab and the cab roof. If I hit a speed hump or even a rough bit of road the Apollo used to bang on the roof and if you looked in the door mirror you could see the line of the pick up sides moving up and down as the chassis flexed. Don't know the truth in this but I've heard that the jap-type trucks with cart springs rely on chassis flex to assist their off-road abilities.

Looking at the chassis rails on the L200 they were fairly puny and they reduced in size further behind the rear wheels - where much of the weight is when you have a demountable loaded.

On my 130 Defender (which has a loadbed capacity of 1.5 tonnes) the chassis rails have over twice the ✖-sectional area and there is no flex at all - even when we are doing serious off roading with the camper on. If there is any truth in the use of chassis flex being used on cart sprung vehicles - the lack of it is certainly not a problem with the articulation on the Defender's coils! To overcome excessive articulation on the road I have a special extra stiff anti-roll bar on the rear which I can disconnect when I need more wheel travel.

Martin

Hmm, well I've had mostly mostly Toyota for a couple of decades and this is the first I've heard of the chassis being used to enhance its suspension,
sounds something cooked up the camo-clad LRO club actually.

What I can (definitely) say is the previous model Navara had something going on, I was never able to see evidence of any movement between tub and cab but noticed rocking of the overcab on uneven road surfaces
and I tried sitting camper on load bed directly-on carpet-rubber mat the lot, and a variety of tie down points,

in the end I moved on and stopped worrying about it and never saw any damage to chassis
(or any contact on roof thankfully)

Don't forget that the buck is mounted onto the chassis using rubber bushes so that could account for the flex.

And bearing this in mind I could only imagine that was the only other explanation,
In my case the rocking was lessened by attaching the two front points down to the chassis rather than all four to the buck

We can discount the rubber bushes for causing the flex as that was my first thought. So I took them out and used metal washers instead. It didn't stop the overcab banging on the roof though!

Martin

Hmm. that sounds very much like a similar situation of a friend of a friend of mine, they had a ec7 skarosser on a fairly new navara , but on holiday a couple of years ago they noticed the truck and camper looked lopsided and assumed it was their packing was causing it, but as it turned out the back end of the truck was buckled.
Nissan apparently washed their hands of it saying the pick up was not designed to carry the camper and s karosser told them to get a better truck, easy if you're loaded ! the truck was written off and they had to sell the camper back to Nolan who then I believe sold it to someone on here.
Those sneaky speed bumps were a pain .