motorhome snaking on the motorway

[carolinewalker]

We have a 5.9 meter roller team t line 590 which constantly snakes on the motorway when the road surface has a cumber due to lorry useage. This has happened at speeds of 55to 60 can anyone suggest why this is happening

[Tracker]

First thing to check is tyre pressures, although this behaviour is not unusual and can be magnified by the overhanging coachbuilt body.

 

This is especially so when the front wheel track width is different to the rear wheel track width such that all the wheels are unable to 'tramline' in the grooves.

 

How long since the van was MOT'd as there may be wear in some of the suspension bushes which can also have an adverse effect.

 

The bolts securing the body to the chassis can also lose their tightness over time, but don't be alarmed, it's unlikely, but getting under and checking them with a spanner will eliminate any chance.

 

Chances are there is nothing wrong and you just have to avoid driving in the groove!

[peacock312]

Suggest you have your tracking checked,especially if from wheel drive

[lennyhb]

Possibly too much weight in the overhead lockers, not heard of it affecting Motorhomes but it plays havoc in caravans makes them very unstable.

[Rayjsj]

It happens to me too, it's the 'tracks' worn into the inside lane of most Tarmac finished motorways and busy A roads. A lot of trucks travel overloaded anyway, and they wear twin 'tracks' into the road, it's the action of your front wheels going in and out of these 'tracks' and the fact that our vans are front wheel drive that can cause 'swaying' it can be scary if you are not expecting it.

My vehicles steering and Suspension are perfectly OK. Ray

 

I'm talking about mild 'Swaying' from side to side, NOT 'Snaking' as known on Caravans, where the 'Pendulum' affect can create a Disaster.

[StuartO]

I experience what might be called snaking in Lane One on motorways when there is visible wear from lorry wheels in the tarmac. I soemtimes have to offset the line I'm taking or even move out into Lane Two to stop it.

 

I dn;t think it is snaking in the sense that is used to describe trailer/caravan behaviour and the cure is different. If a trailer/caravan is snaking you need to slow down (without braking) until it settles and it is important not to delay doing this because it can escalate quickly and cause loss of control. If a MH "snakes" when there are visible wear groves in the tarmac slowing down won't help much but the abnormal movement will stop immediately you get away fron the grooves.

[docted]

Caroline as Ray says the problem is the ruts created by the HGVs. Your wheels are not as far apart as the HGVs so what you are experiencing is your van going fro the right rut to the left rut and back again. You may find things improve if you make a conscious effort to try to keep one wheel in a rut and not go across the lane.

[Robinhood]

.....I suspect that your 'van is built on the Fiat Camper Chassis with the wider rear track.

 

I found the effects of the "spurrinnen" left by heavy vehicles to be much more pronounced when I was running a Rapido on an Al-Ko chassis with a widened rear track.

 

I surmised that the difference in front and rear track meant that there was a much greater likelihood of one or other of the four wheels being "on the cusp" of the depression, and therefore tramlining.

 

(i.e. if one of your front wheels was fully in a track, the rear, not being in line with the front, would be on the edge, causing a rear end "pull". Steer to correct this, and you reverse the situation, and get steering pull).

 

(I appreciate that there can be a slight difference in track from front to rear on standard chassis, but the effect is much greater on vehicles with a deliberately widened rear track).

 

edit: typo

 

 

[lennyhb]

Our last Hymer was on the Fiat Camping Car chassis never never had any stability problems, it was very stable under all conditions.

[Brian Kirby]

As above, the most likely is the ruts or grooves made by trucks. Susceptability to this can be exacerbated by tyre pressures that are too high, especially if you are running at manufacturer's reccomended pressures somewhere in the region of 80psi. Before spending any money on suspension checks I suggest you take you fully laden van to a weighbridge and weigh it, getting the loads on each axle individually. Then contact the tyre maker's technical department and explain what you are experiencing, what sizes and types the tyres are (on the tyre sidewalls), and what pressures you are running at. They should be able to recommend lower tyre pressures for the front, possibly the rear, and you should find that this makes a difference to your van's susceptibility to "tramlining". This has worked for me on two vans, and the difference was very noticeable.

[carolinewalker]

thankyou but she is brand new 2014 so we don,t think any need for checks only purchased in march this year cheers anyway

[carolinewalker]

thankyou what you have said seems exactly what happens tous cheers

[carolinewalker]

Thankyou very much for this advice will do all o fthis as our mh is 2014 so didn t expect this cheers

[Mel B]

I suspect it could be he different tracks and the truck ruts, many years ago we had an old Autosleeper camper on a Commer which had a wider track at the rear than the front, which we really noticed and was exacerbated massively when we towed a car on a trailer!