Bangs and rattles

[Swaltham]

Hi everybody. New member here. Looking forward to some good times
We are on our 4th motorhome (if you count a vw california we had for a few years). After a year with our latest model , a 7.5 metre adria, we've decided to stick with it for a while longer ( unfortunately it hasn't been without problems during that time) and I'm now looking to do some add ons. I don't know whether it's our imagination but this van seems to suffer more from bangs and rattles than any of the others. Even more so than the swift kon tiki we had in late eighties. Hence I'm considering air suspension. What are peoples thoughts on this and especially fitting rear or full? Driving back home on the m20 last week after the tunnel was horrendous. Like driving down a railway track!
Thanks for any replies
Steve

 

[andyelbac]

On the original post on this thread the Funster referrred to the M20/M25. I presume in particular they were referring to the section that runs from Jct 8 (Reigate) all the way through to around Jct 12 (M3)? It's a veritable washboard, made from what looks like slabs of concrete. It reminds me of the corrugated roads you get in the Outback. Every half a second is a nightmare in the MH as you travel over the join in each section. As we live in North Kent it's pretty much unavoidable going west unless we want to queue up for the Dartford Crossing. It's like having a 500lb ape in the back of the MH smashing around with a lump hammer. I'm honestly amazed that we don't end up as a small pile of pieces on the hard shoulder. Every nut and bolt must be trying to make itself loose!. My Q. is, I have VB semi air on the rear and can't say it makes much difference. Is that because I'm running on Michelin Campers at 80psi, front and rear? At those pressures, am I just negating the effect of the air suspension?

 

[Lenny HB]

Is that because I'm running on Michelin Campers at 80psi, front and rear? At those pressures, am I just negating the effect of the air suspension?

Yes, changing for decent van tyres running at sensible pressures will make a huge difference.
Then if you fit full air you will get a similar improvement.
After all that it will still be a hard ride as its a commercial vehicle it will never ride like a car.

 

[Clive Bishop]

Hi everybody. New member here. Looking forward to some good times
We are on our 4th motorhome (if you count a vw california we had for a few years). After a year with our latest model , a 7.5 metre adria, we've decided to stick with it for a while longer ( unfortunately it hasn't been without problems during that time) and I'm now looking to do some add ons. I don't know whether it's our imagination but this van seems to suffer more from bangs and rattles than any of the others. Even more so than the swift kon tiki we had in late eighties. Hence I'm considering air suspension. What are peoples thoughts on this and especially fitting rear or full? Driving back home on the m20 last week after the tunnel was horrendous. Like driving down a railway track!
Thanks for any replies
Steve

I have a Autosleeper Burford on a Mercedes chassis and have just had rear air bags fitted,Very good for pumping up the rear overhang for ferries etc,but made no difference to the squeaks ,bangs,and rattles.

 

[Canucks]

Yes, changing for decent van tyres running at sensible pressures will make a huge difference.
Then if you fit full air you will get a similar improvement.
After all that it will still be a hard ride as its a commercial vehicle it will never ride like a car.

I've only driven one Moho, my current one and the handling seems like a wallowing boat and on some roads on Skye recently the camber made me loose confidence that the van wouldn't roll over. Do they all feel this unconnected to the road surface? Is this why air suspension is worth a consideration?

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[Lenny HB]

I've only driven one Moho, my current one and the handling seems like a wallowing boat and on some roads on Skye recently the camber made me loose confidence that the van wouldn't roll over. Do they all feel this unconnected to the road surface? Is this why air suspension is worth a consideration?

Looking at the van you have I would expect it to handle well, you are probably comparing it to a car.
Our first Motorhome I used to drive it to fast. You can't drive a Motorhome like white van man as its fully loaded all the time, once you manage to slow down and relax it becomes a lot more pleasant.

Air suspension will improve sideways stability and iron out a lot of the crashes but it won't work miricales. IMO well worth the money the boss doesn't think so but the passenger doesn't notice every twitch & bump like the driver does.

 

[dawsey]

Just a note of caution to all those who lower their tyre pressures to significantly less than those recommended by the vehicle manufacturer in the interest of comfort..

Your commercial and commercially derived (van) tyres are designed to cope with significant load range. The higher the load, the higher that the pressure in the tyre must be to support the load. It’s fine to run a van tyre on a generally unloaded van at 40psi, however, full coachbuilt motorhomes are very heavy vehicles, always running close to (and very often at or even over) the vehicle axle and tyre maximum loads. This is why motorhome manufacturers generally recommend the maximum possible tyre pressures, normally 80psi in the rears when cold, which corresponds to approx 90psi when hot, depending on external temperature. It is not too much, it is what the tyre is designed to run at when fully loaded.

The reason for the necessity for a high pressure when fully loaded is to maintain the same tyre sidewall deflection and contact patch (with the road) as when unloaded. This is critical to minimise tyre friction, steel reinforcement fatigue and the heat it generates which if excessive will accelerate tyre aging and lead to unnecessary damage and premature failure.

Unfortunately, the necessary compromise is a harsh ride. It is the consequence of operating the LGV base vehicle at maximum load, at the very edge of its design performance envelope. The harsh ride is much more self evident to owners using these vehicles in the UK due to the terrible condition of the UK roads. It is not the same problem for users in the larger countries of western europe where the roads are generally in a far better state of repair. Another impact of poor road surface (particularly potholes) is also fatigue damage to the tyres reinforcing steel.

Reducing tyre pressures significantly below those recommended by both the vehicle and the tyre manufacturer is most definitely not a solution, is potentially dangerous and in addition, at least in theory, could partially invalidate insurance coverage in the event of serious accident and subsequent investigation. For a very serious accident, where others are harmed, there also exists a risk of criminal prosecution if it could be proven that both the vehicle and tyre manufacturer’s recommendations were deliberately ignored in the interest of driver comfort (ie by what is written in this very public forum).

However, any improvements that can be made to vehicle suspension systems that are focussed on increasing suspension travel (shock absorbtion capability), while maintaining appropriate damping characteristics (for stability) most definitely is a potential solution.

 

[TheBig1]

What makes most noise on motorhomes is the contents. I put pieces of non slip material between plates and bowls. Mugs and glasses wrapped in microfibre tea towels. Especially top lockers, I try to pack with lightweight items to prevent movement. The oven is another sound producer and i wrap teatowels on the shelves to deadeden rattles.

 

[DucatoMan2]

Driving back home on the m20 last week after the tunnel was horrendous.

Yep, that stretch is like 'welcome back to the third world'.

 

[Notts Archer]

Biggest changes we found was reducing the tyre pressures and getting rid of the rock hard camper tyres.

Meanders - my tyres are set to the recommended pressure of 70psi with camper tyres and give a bone shaking ride. Can you tell me what pressure do you now drive on and what non-camper tyres do you have? Thanks.

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[Lenny HB]

Meanders - my tyres are set to the recommended pressure of 70psi with camper tyres and give a bone shaking ride. Can you tell me what pressure do you now drive on and what non-camper tyres do you have? Thanks.

I gave the tyre manufacturer my axle weights and run at the pressure they recommended.
Front 1930kg 56psi, Rear 2300kg 69psi.

 

[Lenny HB]

Just a note of caution to all those who lower their tyre pressures to significantly less than those recommended by the vehicle manufacturer in the interest of comfort..

Your commercial and commercially derived (van) tyres are designed to cope with significant load range. The higher the load, the higher that the pressure in the tyre must be to support the load. It’s fine to run a van tyre on a generally unloaded van at 40psi, however, full coachbuilt motorhomes are very heavy vehicles, always running close to (and very often at or even over) the vehicle axle and tyre maximum loads. This is why motorhome manufacturers generally recommend the maximum possible tyre pressures, normally 80psi in the rears when cold, which corresponds to approx 90psi when hot, depending on external temperature. It is not too much, it is what the tyre is designed to run at when fully loaded.

The reason for the necessity for a high pressure when fully loaded is to maintain the same tyre sidewall deflection and contact patch (with the road) as when unloaded. This is critical to minimise tyre friction, steel reinforcement fatigue and the heat it generates which if excessive will accelerate tyre aging and lead to unnecessary damage and premature failure.

Unfortunately, the necessary compromise is a harsh ride. It is the consequence of operating the LGV base vehicle at maximum load, at the very edge of its design performance envelope. The harsh ride is much more self evident to owners using these vehicles in the UK due to the terrible condition of the UK roads. It is not the same problem for users in the larger countries of western europe where the roads are generally in a far better state of repair. Another impact of poor road surface (particularly potholes) is also fatigue damage to the tyres reinforcing steel.

Reducing tyre pressures significantly below those recommended by both the vehicle and the tyre manufacturer is most definitely not a solution, is potentially dangerous and in addition, at least in theory, could partially invalidate insurance coverage in the event of serious accident and subsequent investigation. For a very serious accident, where others are harmed, there also exists a risk of criminal prosecution if it could be proven that both the vehicle and tyre manufacturer’s recommendations were deliberately ignored in the interest of driver comfort (ie by what is written in this very public forum).

However, any improvements that can be made to vehicle suspension systems that are focussed on increasing suspension travel (shock absorbtion capability), while maintaining appropriate damping characteristics (for stability) most definitely is a potential solution.

Interestingly Carthago recommend much lower pressures for CP tyres than other manufacturers.

 

[dawsey]

From reading this thread, there appear to be significant numbers of folks rolling around using potentially dangerously under inflated lightweight transit tyres on their near 4-ton behemoths in the interest of ‘comfort’.

Extracted from a ‘Motorhome’ magazine feature:

“Many manufacturers provide tables of information, where you can look up your particular brand and size of tyre and find pressure recommendations for a range of axle weights. Search online for the Michelin Technical Guide or the Continental Technical Databook and you should find the relevant PDFs, which you can download.

However, the European Tyre and Rim Technical Organisation (ETRTO) has also issued its own advice on this.

As well as recommending the use of camping-specific tyres (those marked ‘CP’ on the sidewall), ETRTO advises using pressures of 80 psi on the rear axle and following the manufacturer’s advice on the front axle”


Extract from Michelin technical guide on Michelin website:

“Why are CP tyresrecommended for heavy motorhomes?​

If your motorhome is a "Conventional Coach Built Motorhome", "Low Profile Coach Built Motorhome" or "A Class Motorhome" type, the performance of a C marked tyre may be insufficient. We recommend that you use CP marked tyres instead.
Why? Because CP marked tyres have been specifically designed for heavy motorhomes. These motorhome tyres have a higher load index and pressure as well as a reinforced carcass.

Why is a higher load capacity required for CP motorhome tyres?​

Motorhomes are vehicles that generally have a large intrinsic mass (the vehicle itself and the interior equipment) to which is added that of your travel equipment (luggage, bicycles...)

In addition, motorhomes have a high centre of gravity, a sometimes large overhang (the parts of the body between an axle and the end of the vehicle) and an additional load that may be unevenly distributed.

1. Uneven static load distribution (e.g. water tank)
2. Increased load at the rear (e.g. bicycle rack)
3. Load fluctuation due to centrifugal force and point of gravity (e.g. on a bend)

All this is a lot of pressure that all four tyres must be able to withstand over many kilometres. That is why tyres marked CP are better suited to this function than tyres marked C.

CP tyres are recommended by the ETRTO (European Tyre and Rim Technical Organisation) ​

Since 2003, the ETRTO has recommended that tyres used on the type of Motorhomes described above should carry a CP marking apparent in the tyre size description, instead of the normal C marking found on van tyres.

Motorhome tyres with a CP marking, such as MICHELIN CrossClimate Camping, are developed according to the specific load characteristics of these vehicles, in line with the recommendations of ETRTO, to ensure that your vehicle is in the best possible condition for driving and safety.

Motorhome tyre pressure ​

There is another important point to ensure safety and vehicle stability: the tyres of your motorhome must be inflated to the correct pressure. Indeed, the volume and pressure of the air inside the motorhome tyres determine the load they are able to carry.

Motorhome tyres with a CP marking are designed to run at a higher pressure than the pressure for vans (C marking), which gives better handling and increased resistance to the load characteristics of large Motorhomes.

For CP tyres fitted to Motorhomes, the ETRTO advises:

• On the rear axle: the motorhome tyre pressure should be 5.5 bar (80 psi). The maximum load capacity of the tyre must be respected. (Note that the use of a metal clamp in valve or specific high pressure rubber valve is required above 4.5 bar (65 psi)),
• On the front axle: refer to the manufacturer's inflation recommendations indicated on the vehicle and / or its handbook.

 

[Graham Mew]

Hi everybody. New member here. Looking forward to some good times
We are on our 4th motorhome (if you count a vw california we had for a few years). After a year with our latest model , a 7.5 metre adria, we've decided to stick with it for a while longer ( unfortunately it hasn't been without problems during that time) and I'm now looking to do some add ons. I don't know whether it's our imagination but this van seems to suffer more from bangs and rattles than any of the others. Even more so than the swift kon tiki we had in late eighties. Hence I'm considering air suspension. What are peoples thoughts on this and especially fitting rear or full? Driving back home on the m20 last week after the tunnel was horrendous. Like driving down a railway track!
Thanks for any replies
Steve

I’ve. been informed all coach built motorhomes are noisy. My advice is to invest in a pvc (panel van conversion) our IH Motorhome based on a vw Crafter is quiet due to the quality on materials used and the workmanship.£

 

[Blaydon]

On the original post on this thread the Funster referrred to the M20/M25. I presume in particular they were referring to the section that runs from Jct 8 (Reigate) all the way through to around Jct 12 (M3)? It's a veritable washboard, made from what looks like slabs of concrete. It reminds me of the corrugated roads you get in the Outback. Every half a second is a nightmare in the MH as you travel over the join in each section. As we live in North Kent it's pretty much unavoidable going west unless we want to queue up for the Dartford Crossing. It's like having a 500lb ape in the back of the MH smashing around with a lump hammer. I'm honestly amazed that we don't end up as a small pile of pieces on the hard shoulder. Every nut and bolt must be trying to make itself loose!. My Q. is, I have VB semi air on the rear and can't say it makes much difference. Is that because I'm running on Michelin Campers at 80psi, front and rear? At those pressures, am I just negating the effect of the air suspension?

Hi there. during the covid period I had to drive the section of the M25 J8 to J10 every day. Dreadful surface at 70mph but if there was a hold up and you were down to 10 mph it was like driving over a hard ploughed field.

Talking of rattles and bangs, we got a new, and very annoying rattle start up this trip. After a few hours we tracked it down to the boss’s new coat zip banging on the mirror behind the coat hook.
D

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[plug]

Hi everybody. New member here. Looking forward to some good times
We are on our 4th motorhome (if you count a vw california we had for a few years). After a year with our latest model , a 7.5 metre adria, we've decided to stick with it for a while longer ( unfortunately it hasn't been without problems during that time) and I'm now looking to do some add ons. I don't know whether it's our imagination but this van seems to suffer more from bangs and rattles than any of the others. Even more so than the swift kon tiki we had in late eighties. Hence I'm considering air suspension. What are peoples thoughts on this and especially fitting rear or full? Driving back home on the m20 last week after the tunnel was horrendous. Like driving down a railway track!
Thanks for any replies
Steve

You are not alone, when we purchased our Motorhome from West Country Motorhomes we traveled the same road back to Kent and thought it was going to fall apart, the noise was horrendous, but since when re packed the Motorhome with all our goody’s she a lot quieter, found that all the doors needing adjustment, have since fitted rubber buffers to all door and cupboards, and this has help a lot, the problem with these new Motorhomes is they are trying to cut back on the weight,we like other people have had a Motorhome before and the older Motorhomes have better build quality.

 

[Rockcrawler]

You are not alone, when we purchased our Motorhome from West Country Motorhomes we traveled the same road back to Kent and thought it was going to fall apart, the noise was horrendous, but since when re packed the Motorhome with all our goody’s she a lot quieter, found that all the doors needing adjustment, have since fitted rubber buffers to all door and cupboards, and this has help a lot, the problem with these new Motorhomes is they are trying to cut back on the weight,we like other people have had a Motorhome before and the older Motorhomes have better build quality.

I just turn the music up

 

[SteveandSueJ]

I agree with Lenny, van tyres, all season running 60 front, 63 rear on a 3300kg moho. Tyres within load and pressure levels. Previous tyres were new summer tyres and boy did they rattle the van. On first trip since changing them, now down near Provence and the difference in noise, ride quality and confidence is really noticable on all road conditions, including rain...!! very pleased with my decision. I would suggest trying new tyres first, removing the hard cp ones...

 

[Swaltham]

Re that journey home from the tunnel, what made the noises and the problem so acute, was that I knew it hadn't made such a bone jarring racket when we travelled down 3 weeks earlier. And also have it compounded when we were on particular section of the m25. Even the contrast against the superior French roads couldn't account for that. I was convinced I'd broken the van in France. Eventually it dawned on me that Google had taken us down the a2 (?) earlier!!. Presumably because we were staying at Folkestone canc site for the night before

 

[meanders]

Meanders - my tyres are set to the recommended pressure of 70psi with camper tyres and give a bone shaking ride. Can you tell me what pressure do you now drive on and what non-camper tyres do you have? Thanks.

I am running on Divanti 440's at 65 psi all round. Supplied and fitted a year ago by Xspurt tyres in Ipswich. They contacted Divanti while I was there, and they suggested the pressures based on 3500KG.

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[JaG]

We had the same problem with our Autotrail Cheyenne, rattled like a bag of nails. Like others our tyre pressure was 82psi.
Changed tyres to Maxxis All Seasons tyres all round. The difference is incredible. No rattles, smoother ride and 10 ply as well. Tyre pressures are 64psi, and it rides as smooth as a car.
Best thing I ever did and, only £130 each!

 

[bigwood]

The worst rattle on our coach build is the pan cupboard under the cooker not helped because it’s behind the passenger seat.
The 15 miles of the A180 is so bad you can’t hear the radio let alone the pans settling down not helped by the cart springs fitted at the back of our Transit.

 

[Reallyretired]

I have fairly new Michelin campers, and although I tried a reduced pressure at the rear it didnt seem to make much difference so now back at the recommended 80psi. Pressure at the front seems to make the biggest difference to ride so mine are now at 54psi, the recommended pressure for the axle weight and the ride is pretty OK

 

[DDJC]

Re that journey home from the tunnel, what made the noises and the problem so acute, was that I knew it hadn't made such a bone jarring racket when we travelled down 3 weeks earlier. And also have it compounded when we were on particular section of the m25. Even the contrast against the superior French roads couldn't account for that. I was convinced I'd broken the van in France. Eventually it dawned on me that Google had taken us down the a2 (?) earlier!!. Presumably because we were staying at Folkestone canc site for the night before

Your symptoms are what caused us to get the VB semi Air (with compressor and L/R gauges) kit fitted.

We run close or at our MGM of 3500 kilos and the concrete slab sections on the south side of the M25 felt like the bump stops were smashing holes in the chassis. The semi air, pumped to 2 bar makes a difference both in the road noise, and handling. It still bumps, but no where near as much as it used to. Good for ferry/tunnel ramps, speed bumps and inclines as well.

I still have the original 215/R15 Michelin Camper tyres at rear 75psi, front 62psi). After this summer, I will be going for 225 Bridgestone Duravais tyres, and look to run them at 70psi and 58 psi.

 

[bigtree]

The 2 prices quoted there are very interesting. Are either of the suppliers within a reasonable distance to me ( Yorkshire)?

Northwich in Cheshire.

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[bigtree]

I paid £8k for the full VB package on a Fiat chassis at the beginning of the year.

Where was that and did it include self levelling and emergency valves ?

 

[Guigsy]

Where was that and did it include self levelling and emergency valves ?

A&E Leisure. Yes and yes.

 

[Lenny HB]

From reading this thread, there appear to be significant numbers of folks rolling around using potentially dangerously under inflated lightweight transit tyres on their near 4-ton behemoths in the interest of ‘comfort’.

Extracted from a ‘Motorhome’ magazine feature:

“Many manufacturers provide tables of information, where you can look up your particular brand and size of tyre and find pressure recommendations for a range of axle weights. Search online for the Michelin Technical Guide or the Continental Technical Databook and you should find the relevant PDFs, which you can download.

However, the European Tyre and Rim Technical Organisation (ETRTO) has also issued its own advice on this.

As well as recommending the use of camping-specific tyres (those marked ‘CP’ on the sidewall), ETRTO advises using pressures of 80 psi on the rear axle and following the manufacturer’s advice on the front axle”


Extract from Michelin technical guide on Michelin website:

“Why are CP tyresrecommended for heavy motorhomes?​

If your motorhome is a "Conventional Coach Built Motorhome", "Low Profile Coach Built Motorhome" or "A Class Motorhome" type, the performance of a C marked tyre may be insufficient. We recommend that you use CP marked tyres instead.
Why? Because CP marked tyres have been specifically designed for heavy motorhomes. These motorhome tyres have a higher load index and pressure as well as a reinforced carcass.

Why is a higher load capacity required for CP motorhome tyres?​

Motorhomes are vehicles that generally have a large intrinsic mass (the vehicle itself and the interior equipment) to which is added that of your travel equipment (luggage, bicycles...)

In addition, motorhomes have a high centre of gravity, a sometimes large overhang (the parts of the body between an axle and the end of the vehicle) and an additional load that may be unevenly distributed.

1. Uneven static load distribution (e.g. water tank)
2. Increased load at the rear (e.g. bicycle rack)
3. Load fluctuation due to centrifugal force and point of gravity (e.g. on a bend)

All this is a lot of pressure that all four tyres must be able to withstand over many kilometres. That is why tyres marked CP are better suited to this function than tyres marked C.

CP tyres are recommended by the ETRTO (European Tyre and Rim Technical Organisation) ​

Since 2003, the ETRTO has recommended that tyres used on the type of Motorhomes described above should carry a CP marking apparent in the tyre size description, instead of the normal C marking found on van tyres.

Motorhome tyres with a CP marking, such as MICHELIN CrossClimate Camping, are developed according to the specific load characteristics of these vehicles, in line with the recommendations of ETRTO, to ensure that your vehicle is in the best possible condition for driving and safety.

Motorhome tyre pressure ​

There is another important point to ensure safety and vehicle stability: the tyres of your motorhome must be inflated to the correct pressure. Indeed, the volume and pressure of the air inside the motorhome tyres determine the load they are able to carry.

Motorhome tyres with a CP marking are designed to run at a higher pressure than the pressure for vans (C marking), which gives better handling and increased resistance to the load characteristics of large Motorhomes.

For CP tyres fitted to Motorhomes, the ETRTO advises:

• On the rear axle: the motorhome tyre pressure should be 5.5 bar (80 psi). The maximum load capacity of the tyre must be respected. (Note that the use of a metal clamp in valve or specific high pressure rubber valve is required above 4.5 bar (65 psi)),
• On the front axle: refer to the manufacturer's inflation recommendations indicated on the vehicle and / or its handbook.

Try telling that to all the posh Motorhome manufacturers. N & B, Morelo, Concorde etc., they all use standard van tyres. I not noticed them lining the the sides of the road with blown tyres.

When my new van arrives I'm hoping to do a deal and get the tyres swapped no way do I want camping tyres on it. I like tyres with some grip and a decent ride.

 

[nickq]

I just purchased new tyres and contacted continental for the pressures. I went for a higher load rating tyre this time as the 116 were very close to the max possible axles weights, so I went with 118 for some extra safety margin since I uprated to 3850 with driverite air.
I gave continental my maximum possible axel weights (since I would rather be conservative) and they came back with 50.7psi (1850kg) for the front and 72.5psi (2240kg) for the rear. However I noted that even their own data states with the CP tyre the rear should always be 80psi, not sure why he missed this point.
I'm now running 55 in the front and 80 in the rear. If if followed the original van manaufacturer's guideline then it would be 79 both front and rear (in a 116).

Also Continental agreed that when stored without moving for long periods like over winter, then should inflate the front also to 80 as it helps stop the tyre from becoming deformed.

Incidentally these are way different to the original Michelin CPs I had from 2017. They even feel like rubber instead of plastic.

 

[bigtree]

A&E Leisure. Yes and yes.

That’s interesting as I had to haggle to get down from £8.5k from them.

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[Guigsy]

From reading this thread, there appear to be significant numbers of folks rolling around using potentially dangerously under inflated lightweight transit tyres on their near 4-ton behemoths in the interest of ‘comfort’.

If the tyres are correctly load rated for the axle, then they'll be safe. Load is load, it doesn't matter if it's sand or a bed and bathroom.

My van tyres are rated as 121, which is 1450kg per wheel. Far more than the 2000kg I'm allowed to carry on my rear axle. The tyre manufacturer says I can run them safely at 50psi at my maximum load.