Buckled Rear Wheels

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Soldato
Joined
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Location
Leicestershire
Took my car to ATS this morning to get 4 new boots fitted.

The guy said that the rear wheels are slightly buckled. I asked him if it was worth getting them aligned still to which he said no. He said it's a common thing with heavy cars (S-Max) and 18" wheels... I don't suppose it helps by running over pot holes with the suspension in 'Sport' Mode?

So I took it to Tyres Galore in Leicester for a second opinion, he jacked the car up and spun both rear wheels and said that they are both slightly buckled - but not exactly buckled - more flat spotted.

I asked him if it was worth still getting the wheels aligned on my car and he said that yes, it would be fine and he gets cars in quite often with flat spot buckles and cars with wheels which are buckled a lot worse than mine...

So it's the old being told one thing and then another etc. so I thought I'd ask on here for a third opinion on what the consensus is. Any advice much appreciated.

I am taking my car this afternoon to get MOT'd at my independent garage so I will ask him the same thing but it's always nice to get as many opinions as possible!
 
I dont like any sort of buckle on alloys.

make the car unstable and wobble... not the mention the extra stress put on bushings from the added vibrations.
 
[TW]Fox;29835040 said:
A decent alloy wheel specialist can repair slightly buckled wheels.
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Interestingly both the ATS guy and the Tyres Galore guy said that they can be repaired but that it wasn't worth it, and they wouldn't bother. :confused:
 
Slightly off topic but why does an s-max have a sport button? Back on topic whats a flat spot buckle? Flat spot to me is on a tyre, or is it due to a flat spot on tyre thats caused the alloy to buckle:confused:
 
theone8181 said:
Slightly off topic but why does an s-max have a sport button? Back on topic whats a flat spot buckle? Flat spot to me is on a tyre, or is it due to a flat spot on tyre thats caused the alloy to buckle:confused:
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It has Comfort, Normal and Sport Suspension modes. I thought the same regarding the flat spot term, used to hearing it in F1 a lot to do with tyres - never heard of it being mentioned with alloys before but then I'm no expert on the subject!
 
It'll be from an impact like a pothole. That will have pushed in part of the rim so it's no longer circular and has a flatter area. If this was to happen and cause an easily visible flat area you'd likely feel it, but a bigger impact - or a weakness in the wheel - could have just caused the rim to crack instead.

Depending on how much it is to be fixed, you might be better for the long term with a single replacement. Although I wouldn't know how they'd repair it without just 'forcing' it back into shape. *can't think of a better word right now. :p
 
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I had a flat spot buckled alloy and it only cost £75 to get it welded and re shaped.

Basically the wheel gets hit hard enough that it gets knock out of shape (it's no longer round it has been flattened off where it was hit). If it gets hit hard enough it can split on the centre of the flat spot.
 
A normal buckle is where the lip of the wheel is bent in or out from the face of the wheel.

A flat buckle is where a force has pushed a section of the wheel lip inwards towards the centre of the wheel only, so it isn't entirely round any more. Had the same happen on my Mondeo, but luckily a second hand alloy for that was only £30 from the scrappy
 
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Thanks for the info guys. Sounds like I will be going for two new alloys - I've managed to find them for £215 each so thats not too bad, when you factor in safety and cost against getting them repaired...

Also found this from another forum... makes for a very interesting read if anyone else is thinking about getting their buckled wheels repaired

Repair of light-alloy wheels

Unfortunately, repair of light-alloy wheels is still very common. This information explains why it would be better to steer clear of the repair of light-alloy wheels.

The following information was obtained from various Internet pages addressing the repair of one-piece light-alloy wheels:
1.) Damaged rims are heated across their entire area and then repaired by means of a rolling procedure.
2.) Subsequent curing ensures that any differences in strength remain within the tolerance range.
3.) The metal alloy on the damaged wheel is analysed, and we can assure customers that the material used in repairs in which parts are welded on or into the wheel will be identical to the original material (alloy, strength, material quality).

We will refute the above statements one by one:
To start with, here is an excerpt from an information leaflet published in March 1999 by the German Association of Tyre Retailers and Vulcanizers (Bundesverband Reifenhandel und Vulkaniseur-Handwerk e.V.). In this case, a badly damaged wheel (localized deformation of inner bead seat caused by shock load, no incipient cracking) was repaired at a "tyre clinic". The wheel was then intensively inspected with the following result:
1.) Machining of the rim beads caused dimensional changes exceeding the tolerance limits, in particular regarding the following functional dimensions: circumference of rim bead, hump circumference, rim flange radius and outer diameter.
2.) At the same level of local load, local heating and deformation reduces energy absorption by approx. 25 % . In practice, this change in material properties results in increased deformations caused by driving over obstacles or over grooved road surfaces such as rail crossings, transversal grooves, etc.
From our point of view, we therefore advise against such repairs
Source: BRV repair of aluminium rims)

On its website, the EUWA (Association of European Wheel Manufacturers) also strongly advises against rim repair in the following words:
"Repair of a damaged rim or disk by heating, welding or addition or removal of material is absolutely forbidden.
No guarantee on repaired parts is acceptable since such changes may introduce additional stresses in critical high-stress areas.
Wear on rim flanges (top of the flanges) can be tolerated up to a maximum of 10 per cent of the initial thickness of the rim material." (Source: www.euwa.org)

After in-depth tests and inspections performed in December 2004, wheel certification experts at TÜV SÜD Automotive agreed with this statement. Further information: www.tuev-sued.de/automotive

Why is "heating" and "welding" or "addition of material" so dangerous?
As a matter of principle, a deformed rim cannot be restored to its original state. Every material changes its properties once the yield point, i.e. the point prior to which a material deforms elastically (referred to as ReH in the diagram), is exceeded, so that the wheel is permanently deformed (e.g. impact). The higher the deformation, the less force is required to cause further deformation (exceeding of yield point (ReH) or ultimate strength (Rm). Material strength thus decreases! The material properties cannot be restored to those of a new wheel (not even by annealing and recrystallization).

On wheels, welding has several adverse impacts on the material. Firstly, localized heating causes thermal stresses (i.e. the material is subjected to internal stresses in addition to the stresses occurring during operation). Additionally, material composition is changed by separation and crystallization processes (brittling caused by quick cooling, inhomogenity caused by diffusion and the addition of additives). The strength of a welded wheel thus differs significantly from that of a new wheel. Even repeated thermal treatment cannot restore the original properties of the wheel.

With respect to metal alloys, the following can be said:
Determining the alloy composition of cast rims within the scope of repair work is completely impossible. To identify alloy materials and their proportions, material would have to be sampled from several locations of the rim. This would result in complete destruction of the wheel, which would no longer comply with the inspected original state (material sampling).
Even renowned casting technology institutes cannot always accurately identify alloy composition in the melt, as local material composition is largely determined by the casting process. Basically, only a few institutes at universities and research facilities are able to undertake analyses of the melt (composition of cast).
The costs of such analysis considerably exceed the purchase price of a new wheel.
Depending on wheel design and dimensions, cooling rates differ across the wheel area. Mechanical and technological properties (including crystallization rate) are established during the casting process
Additionally, the production of "repair parts" whose material composition is identical to that of the area into which the part is to be welded, is simply impossible. Even if it were possible, it would result in the material changes described above

Made some interesting reading
 
£60-80 per wheel to fix as estimated over the phone by an alloy repair company in Leicester... or £400 for two brand new wheels...

So £160 tops for repairing them means a saving of £240.

I don't know whether to get them repaired or get new ones now. I guess £240 is quite a saving but it seems people are 50/50 as to whether they'd repair wheels or bin them and get new ones regarding the strength of the wheel after the repair etc.
 
I would get them repaired, and make sure not to drive over bumps too fast or fall down pot holes.

if you look after them then they will look after you
 
If you are regularly travelling badly pot holed roads, it might be worth downsizing to 17" (or even 16") rims and the slightly higher profile tyres that these would use. Especially if you are looking at buying new wheels anyway.

Also isn't the comfort/normal/sport setting more a steering/throttle response setting rather than a suspension setting (as didn't think the SMAX had any kind of height adjustable / electronic dampers)?
 
Thanks guys, Armageus, it definitely is a suspension/dampers thing as I can feel the car lift slightly in comfort mode and lower slightly when changed to sport - more noticeable on an A road though rather than driving around town when feeling the change.

I just spoke to the lad at ATS again and he said that one of the wheels on the passenger rear is buckled/flat spotted pretty badly - it's about 3 or 4 inches where it's buckled on the inside of the rim -

Surprised I didn't get any steering wheel shake when they were fitted to the front then.

He said he wouldn't advise getting them repaired due to heat up/cool down process which then makes the wheel more brittle than before and liable to cracking.

I'll just take it to the guy in Melton today so I can actually see the wheels for myself more than anything and see what he says about the methods to repair... seems to be a bit of scaremongering about perhaps with regards to repairing alloys.
 
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Thanks guys. ^

Welllllll I drove there, completely in two minds and not knowing what to do - I was almost agonising over what to do - rocked up to this alloy place, and got cold feet, sat in my car and phoned my Dad and we both agreed not to get them repaired, it just doesn't sit right with me (getting the alloys heated up and straightened out etc.) I just can't see how it's going to be as strong as before and heated metal is surely always going to be weaker after it's been subjected to such strong forces of load and heat. And even if I did do it it's going to be the best part of £160-200 but the wheels new cost £400 so it just doesn't make sense whichever way I look at it.

The car recently passed it's MOT (yesterday) with no advisories, I felt what the car was like on the way to the alloy place today (about a 20 minute drive along smooth roads - a couple of potholes were noticed along the way tho, darn things!) and the car feels good, it feels smooth enough to drive... there's no vibrations in the steering wheel but then the wheels on the front are fine and balanced - there's a slight tendancy to steer to the left - it's very slight, if I take my hands off the steering wheel - I think - it may have been a slight camber in the road but I still *think* there's a slight lean to the left so it might well be a good idea to get the wheels aligned.

When I got home I parked the car at the top of the drive on a slope so I could get underneath and visibly see the inside of the rear wheels - the lad at ATS said it's a 3-4 inch "bad" buckle on the passenger side - I couldn't see anything :confused:

I took some pictures - I realise though that you may not always be able to see a flat spot unless the car's jacked up and your level with the wheel spinning?

Anyway, fwiw here's the photos... I know that you can't see the entire wheel so it's probably voided the whole idea of taking photos but two stop the car and not see anything visible on either wheel....Or can you see where the flat spots or from looking at these pics? Should I still be able to get the wheels aligned ok? ATS said because of the buckled wheels the rears won't balance up properly.



















 
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I can't see anything obvious from those pictures - certainly nothing too serious.

ATS were likely exaggerating, the other tyre place - maybe there could be something minor, but the fact he described it as "flat spotted" doesn't exactly fill with confidence.

At this stage I would just get an alignment done, and then run them until you notice anything definitive - for all you know they could have been like this for 10k+ miles or whatever you got out of your last sets of tyres, and you haven't known.
 
Armageus said:
I can't see anything obvious from those pictures - certainly nothing too serious.

ATS were likely exaggerating, the other tyre place - maybe there could be something minor, but the fact he described it as "flat spotted" doesn't exactly fill with confidence.

At this stage I would just get an alignment done, and then run them until you notice anything definitive - for all you know they could have been like this for 10k+ miles or whatever you got out of your last sets of tyres, and you haven't known.
Click to expand...

Yep I think that's a good idea, will get the alignment sorted next week.
 
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