Al-Ko Axle suspension failure (Bailey)
I have my 'worry hat' on again after reading issues on caravan blogs around the longevity and quality of the rubber suspension in Al-ko axles. The complaints raised discuss the need to replace rubber triangular suspension bits due to 'lop-sided' vans, some that bad that the tyres are rubbing on the wheel arches, requiring roadside recovery. Some have been replaced under warranty, but most have not. It requires the axle to be taken off the van and refurbished or replaced at quite a high cost in relation to the part. £1500c. And quite a long time off the road.
Various rationale is given why these rubber inserts fail, and as expected Al-ko refer to overloaded axle limits as the main culprit. Although there are plenty of comments around quality of the original part when they are replaced under one year old! It appears to affect single axle vans in the main.
Whilst I don't currently have this issue I would prefer not to have the van laid up for weeks if it occurred and wonder if there is a way to supplement the caravan axle by replacing the OEM shock absorbers.
I have never been entirely happy with the road bouncing my Unicorn 2 Valencia has shown since buying new in 2014, but put this down to the very high tyre pressure (60lbs) providing a very firm ride. But do have concerns that this design (single axle @ 1500kg) is wearing the bushes in the axle. Has anyone improved the fairly basic caravan axle/shock combination?
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I also have the same concerns and have done some digging.
A lot of research has been done by Bailey in conjunction with Bath University. They have studied stability and chassis design. Back in 2009 when Bailey was developing Alu-Tech they did accelerated life testing on Vans at Millbrook test centre. Which was used to Market Alu-Tech - but that was not the whole story!!
The Link below is to a student Thesis on chassis design concepts and testing but it also contains a section of the 2009 Millbrook testing done by Bailey.In Section 3.5 onwards of the report.
The worrying facts here are that the test was to simulate only 6000 miles of use, the van was unloaded and the Alko chassis failed adjacent the axle.
The report linked below could be useful information for those who have suffered axle failure, Bodywork distortion, Internal furniture damage.
I believe this is applicable not just to Bailey but any van on an Alko chassis.
A lot of good information could be gleaned from this report by a vehicle chassis engineer, some other other conclusions are that - the rubber suspension and shock absorber do very little to reduce impact to the chassis and structure, in fact the tyre does most of the "suspension" The caravan floor is a weak point not being stiff enough. Also that there are much better suspension sytems available ie those swing arms from the 1960 -70 -80s.
LINK
http://opus.bath.ac.uk/36474/1/UnivBath_MPhil_2013_J_Lewis.pdf
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Oh I missed a crucial point. The chassis failed after only 47% of the accelerated life testing had been completed. Not sure what that equates to in miles but less than 6000, Probably closer to the 2000 that the student was asked to design to (2000 miles per year over 15yrs)
And Testing is on a Series one Valencia
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Hi, this is a concern to me as well. We are just about to leave for Spain in our 2013, Bailey Valencia, and I have noticed how close the inside mudguard is to the top of the tyre. There's only about half an inch of clearance! I don't believe the van is overloaded. I have heard that Bailey have issued warnings of this problem on new caravans but nothing yet on the older caravans!!
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I believe this to be an Al-Ko issue rather than being specific to Bailey - other manufacturers should be joining the discussion.
Some 6 months ago we sold a 2014 Swift Challenger Sport . We had a number of issues regarding quality - but we also had concerns regarding the wheel arch clearance, and also the stability of a single axle for a caravan over 7 metres long with a uprated MPTLM of 1500kgs. We too had clearances in the off-side wheel arch of less than an inch. I wonder now if the stability issue was due to the imbalance of the axle? Maybe the club tech team could be coerced into action!
Snoopyrees1 - maybe a visit to your nearest weighbridge will settle the weight concerns for you?
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This is an excerpt from the Bailey tests in 2009 via J Lewis thesis.
If you read the link and section I refer to in above post there are pictures of the chassis.
Standard vehicle accelerated life test to simulate 6000 miles.The test was halted after 47% completion due to stress cracks in the chassis adjacent the axle making it unsafe to use.
Unfortunately it is not stated which parts make up the 47%
TEST SPEED CYCLES DISTANCE mls
Pave 10mph 231 207.9
Kerb strikes 5mph 63 31.5
Hill route N/A 30 63
Twist humps 10mph 99 118.8
High speed N /A 51 214.2
Potholes 15mph 24 21.6
Total miles 6570 -
It's now 18 years since we had a problem with our Alko suspension. It's a long story, and I've posted some details about it in the other thread on this topic which I'd suggest you read as there are many other complainants and most of the ones I've read seem to be the off-side axle (as was ours).
Here's the text from my post:
Though our caravan is now sixteen years old, we noticed a 'lean to one side' within a week of taking it home brand new. Fortunately, at the time, it was sorted out by Alko/Swift without cost to us, and done very quickly because we were due to go on holiday. It was actually done twice - a replacement axle assembly sent up to our dealer by Alko had the same problem (twisting of the inner rubbers which given the 'suspension' effect) as the one it replaced, so at that point Swift insisted it be towed back to Alko on a low loader, repaired with a complete new axle assembly, not refurbished, and returned within the same week - and it was. The whole thing was sorted out within two weeks by our fantastic local dealer, Swift, and Alko.
There are many other posts about what is obviously an on-going design problem. We were told a 'whole batch' was faulty!
If it's a similar problem of a 'lean', I wouldn't expect it from a caravan of any age and think it's an inherent fault, and would fight hard, quoting posts such as this one: Alko axle problems and other similar ones which you can find by googling.
To add more detail, our caravan had only been used for two nights near the dealer we bought it from in Lancashire, and then taken back to storage near Leeds, and when we picked it up the following weekend we noticed the 'lean'. It wasn't towed back to Lancashire, but to our nearest Alko agent who happened to be Dickinsons in Bradford. The dealer in Lancashire wasn't particularly interested, so we phoned the company we'd always used for our previous caravan services - who were just incredibly helpful. The axle was removed and sent down to Alko, initially, for new rubbers to be inserted.
Our Swift has shock-absorbers, too (being built for the Dutch market) so the problem wasn't due to overloading, speed, potholes, or any other nonsense which seems to be quoted now to 'explain' the problem. We were told categorically that it was the triangular suspension rubbers which were 'faulty'. The explanation I think we were given was that sometimes when they are inserted into the axle they twist, and then there is no 'suspension effect' at all. I am sure that Chris Lancaster, the service manager at Dickinsons will remember 'the Swift Speedbird with the leaning axle' and perhaps has some documentation relating to our problem all those years ago.
There are many people having similar problems - it seems to me that someone needs to get together this whole group of people having the same problem! Sheer weight of numbers may lead to a more honest and more permanent solution to so many people's Alko axle problems. It may also stop the nonsense of telling everyone the same thing - as if they are the only people with the problem - when it is obviously much more widespread.
I'm posting this now, because I want to go off and look at some other links, but will revisit this thread shortly.
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Thanks ValDa for your information, and the link to previous issues that clearly I've missed in CT. I've now caught up.
I've checked my van this morning and the 'shock-absorbers' appear to be black and not red as stated in other posts. Is this significant? I can only look at one side until I move the van, which is under its winter cover.
I was hoping that uprating these would help the situation - if the triangular rubber has not moved already.......
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So perhaps if most if not all of the suspension is actually provided by the tyres then to enhance the lifespan of the caravan they could be used at a slightly lower pressure to give more pliability.
The tyres would need replacing more often due to the extra stress applied to them, but that is far more easily done than replacing an axle, vastly cheaper, and takes under an hour.
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Here's the explanation of the various colours of Alko Shock Absorbers - the colour relates to the category of load - and if yours are black then it looks like they are already the heaviest duty ones.
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For some reason I can' edit my last post.......I said I had black shock absorbers, but check again and they are the red ones......is it normal you can't edit previous posts???? but have to fill the page with updates?
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This occurred to me initially, but previous posts around tyre safety stated that the level of the correct pressure was integral to the safe running of tyre. In other words, the tyre fitted must be inflated to the level recommended to cope with the weight of the van!
I remember raising this issue when I first picked up the van as 62psi is extremely hard. In my view adding to the early failure of the rubber inserts.....
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When I checked the weight of my Lunar Clubman I found the load on the off-side tyre was several hundred Kg more than the load on the nearside, which surprised me at the time.
On reflection I should not have been surprised as all the heavy bits, heater, oven, fridge, microwave and toilet are installed on the off-side of the caravan.
Unfortunately I have lost my record of the measurements but I do wonder if such design contributes to the suspension problem. Further I wonder if I should be running the tyres at different pressures.
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Perhaps the tyre pressure re-calculation should be done using data from the tyre manufacturer rather than from the caravan maker?
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Thanks Viatorem for the link to the thesis, it was most interesting. The conclusion is for manufacturers to revise and adopt the findings, which in the main refer to the outdated suspension and chassis to a more 'car-like' construction. Interestingly the fitting of the shock absorbers, had little to no effect on the suspension, with the rubber torsion taking most of the bumps.......... 5 years ago and nothing has happened! speaks volumes. Great read - thanks.
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Regarding rubber suspension, shocks and tyres. I am not an expert but here is my vaguely informed opinion.
Having some experience in engineering and looking at the design of the alko suspension in conjunction with the study by J Lewis and images of sectioned axle tubes on the web I would suggest that either rubber of an incorrect hardness specification was used or the rubber was not fully cured = too soft = same result.This would explain a bad batch. Twisting rubbers on assembly looks unlikely from the design of the axle tube, Probably more likely individual vans. This is for cases of sagging suspension with no signs of chassis damage.
Again referring tho the JL report the red alko shock absorbers when tested in 2013 were not correctly tuned to the characteristics of the rubber suspension. As shown the suspension cannot cope with pothole type impact without transferring the shock to the chassis and van structure. This may have been corrected since as I am sure that feedback would have been sent to Alko. Maybe!
Reducing tyre pressure to help is a dangerous approach which could lead to tyre and or wheel damage. Check the picture on page 55 of the thesis. It shows a 2009 test with a Bailey Valencia unloaded hitting a "standard" pothole at the MIRA test track. The tyre presumably correctly inflated is compressed to the alloy rim. In fact it looks to me if the rim is damaged but that could be the poor photo.
Sagging due to rubbers or chassis is potentially dangerous as the handling and stability of the van in cornering will be affected. Also in the rubbers case the available suspension travel will be much reduced again impacting handling.
I can't find evidence at present but I am beginning to think that there is a tendency for van manufacturers to run very close to the chassis and especially the axle limit on single axle vans, leaving little safety margin on load. Combined with the state of roads it is feasible that probability of damage is increased. So cost saving and reducing MG weight are contributing factors, I guess the engineers complained but were constrained by budget!
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why do all manufacturers us Alko products. why not use Indespension units as these are not an axle going from one side to the other but individual units and can be replaced much cheaper. on there website they sell a pair of braked 1500kg limit for less than £400 and come with hubs brakes etc etc and just bolt direct to chassis so 4 units would be ample for the heaviest of van. other weights are available. seems a better option to me and would also cut costs on production and repairs both in parts and labour. just a thought.
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I have come to the conclusion is that the Alko axle is overloaded because almost all makes fit appliances on the offside of the van,this extra weight is causing the axle to fail .
if you look at the 2018 models a lot have now started balancing the weight by fitting fridge and microwave on the nearside, unfortunately there are many caravans with this unbalance and we as owners have had to pay for Alko axle replacement due to a design fault.
The caravan design is at fault and customers should be compensated for cost involved in rectifying the failure, however even with a new axle fitted the replacement axle will again need attention as there is too much weight on the offside of the van.
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I agree. The axle will be graded as taking a total load, rather than a specific load on each axle.
Makes our careful disposition of equipment a bit spurious!
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I have read a copy of a letter from Bailey that states
"Bailey has made the decision to replace the axles on .......(2014 to 2016 Unicorn III Cadiz, Madrid, Valencia and Vigo)"
This document is posted on several forums but due to possible copyright issues I'm not sure I can repost it here.
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We have a 2016 Bailey unicorn Vigo currently with bailey at Bristol having a new axle fitted it went in for its second service to our dealer in Bradford who found scuff marks on offside wheel arch liner this was end of December alko came to inspect it then bailey came to pick it up take it to Bristol did weight tests and fitted a new axle just waiting for it delivering back obviously we were upset and quiet annoyed that a new van had this problem but both our dealer and bailey have been great no question of overloading etc all done under warranty so I would check under the wheel arch if you own a bailey unicorn 111 think it’s widespead issue
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Can you direct us to the blog/websites you have seen this please
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Thanks for the link MrBigFeet, the information discussed and concluded on the FB page is very enlightening. To summarise, my understanding of the ‘axle’ issue after reading the pages are as follows:
- Bailey will replace axles that have dropped without prejudice or examination or cost. But only series 3 single axle Unicorns. presented to a dealer. There is a copy of this on the FB page.
- Dealers have a check list specifically for this issue showing how to measure the drop. It should be a gap of 25cm from top of tyre to bottom of inside wheel arch. A copy of this simple test is also on the FB page.
Overloading/Axle design
Whilst some people of Series 2 are experiencing the issue, they are in the minority compared to the number who have Series 3. The conclusion by many on the FB page; that the Series 3 is leaving the factory already at maximum weight, with no allowances for personal payloads. Effectively the owner (unknowingly) loads the van with personal effects and now becomes overloaded. This is bourne out with facts and figures from owners with the problem. The Series 4 is considerably lighter by comparison.
Interestingly ALKO (comments from owners) continue to deny Axel failure due to components and blaming Bailey making the Series 3 too heavy for the supplied Axle! Which may have induced them (Bailey) to offer the free replacement.
whilst I have no affiliation with the FB Page, if this update concerns you, join the page and read the many posts on the subject, and come to your own conclusions.
Disappointed that the free replacement is only S3, but until I take the cover off my S2 van won’t know if I’m really affected. I’m satisfied that the ex works weight of my S2 is very near the designed weight after having it weighed a couple of years ago, but it has made me very cautious of how much I carry in it, keeping well below the payload. It is a pain, but if it helps lengthening the life of the axle I’ll put up with it.
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As I said earlier in discussions about Alko failures, our Swift Speedbird axle was replaced back in 2000 when it was new, because of lack of clearance on the 'passenger side' wheel arch. In our van this is where the heavy equipment is located - fridge, fixed bed, kitchen cupboards, etc. It was replaced without quibble by Alko and Swift, and has since done more than 60,000 towed miles without any problems.
The fault with our axle was acknowledged to be the failure of the suspension rubbers, which had twisted inside the axle casing, giving no suspension effect at all.
I must admit it beats me how caravans, which are designed for living in by four people, can be considered overloaded if just a few extra bits and pieces are loaded on board! After all we have everything on board, and then we climb in as well!
Are caravans actually 'fit for purpose' these days?
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In a word, no.
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Thanks PaulandCheryl for the Facebook synopsis, personally came off FB 8 years ago. (My own reasons)
Could I just check with you the clearance stated 25cms (10”) seems excessive Do you mean 25mm?
will get a mate to check FB for me...
Regards
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