Component parts and Assembly
Use of Spare Wheel, wheel Designation & Tyre Care
Most of us that have alloys fitted will be carrying a steel standard spare wheel, it is important to remember that you also want a set of wheel bolts 4cm long Nut size 17mmWHICH MUST BE USED WHEN FITTING THE STEEL SPARE, WHERE POSSIBLE FIT THIS TO THE REAR OF THE CAR , AND WHILE IT IS FITTED DRIVE AT A REDUCED SPEED Remember your wheels may not now be balanced.
suitable for that wheel. In my case the wheel bolts were stowed in a bubble pack which is stowed in the wheel bolt holes
Do remember to check they are present before getting caught out!
The wheel it's self does carry a warning about
the bolts provided with your alloy wheels. Which in the case of Mercedes-Benz aluminium wheels are 6cm long. Nut size 17mm
Also the New Wheels must be suitable for the 'A' Class you intend fitting them to, if made by Mercedes-Benz will have their emblem (Triple spoke) on them, if this is the case the long wheel nuts Part Number. A000 990 1007
(A above right.) will be suitable for those wheels.
Wheels not supplied by Mercedes Benz must be fitted with wheel bolts supplied by that manufacturer.
A failure to comply could at best, result in your car failing it's MOT, at worst causing an accident with serious or fatal consequences.
Now having told you that you would expect any car in the vicinity of my home to have all the right things on it.
I was horrified to be told by the garage that carried out the M.O.T. on my wife's 'Smart' this year (Sept/2008) that they believed the car to be fitted with the wrong wheel bolts.
I immediately looked into this and with the expert and professional help of 'Sam' at 'Serve-u Motor Services' was able to confirm that the information was correct. The new and correct bolts are now on order and will be fitted as soon as they arrive. Now I'm pleased that my wife uses her car so little, having only completed about 2000 miles in the last 4 years.
Needless to say I will be having a 'wee word' in the ear of the Managing Director of the 'Smart' Garage now located at East Preston in Sussex, who sold my wife the car and boasted at the time at how well the special wheels, they had fitted looked! Pity they hadn't spent a bit more time and got the correct bolts for the wheels fitted or at least ensured the one's supplied which should have been part of the wheel fitting kit were fitted.
Sam thank you, you could well have saved an accident and have almost certainly saved my wife the price of a new set of wheels in the longer term due to damage the incorrect bolts could cause.
Purchasing second hand/used wheels
The same problem could confront you if you purchase second hand/used wheels from such places as e-bay, always confirm with the seller that the wheel bolts are being supplied with the wheels?
this also applies where you are purchasing Mercedes-Benz aluminium wheels, to fit on a car that's currently fitted with steel wheels, you will want a complete set of 20 bolts which if not purchased with the wheels will set you back £50-£60 + so check before you commit to purchase.
One mail sent to a seller with 17" Sabrepower chrome alloy wheels for sale came back with the answer 'sorry no bolts' How sellers can expect to sell special wheels without bolts beats me.
However another mail I sent to Parts@dronsfields.co.uk, Lee,
Ref wheels for sale on e-bay:-
Can you confirm that the wheel bolts are supplied with the wheels you have for sale?
mail recd, 'Which alloys are you referring to? If itís the 'A'-class ones they come minus wheel studs but your original studs will fit'
Lee was very forth coming with further information and if purchasing his wheels I would be more than happy that they were genuine MB wheels, and if replacing the aluminium wheels currently fitted to my car my bolts would as he says be satisfactory. However bear in mind my point about replacing them on a car fitted with steel wheels, Even though they are MB wheels the bolts will need replacing.
Retain one set of your original bolts for the Spare steel wheel.
And remember just because they have been removed from a Mercedes car does not make them MB spec wheels so do check.
Also on e-bay are 16 bolts for sale where it is claimed they are suitable for an 'A' Class!! Great, so that will fit 3 wheels!! But apart from the one remaining bolt you have left over, what are you going to fit the 4th wheel with?? I make 4 wheels x 5 studs = 20!!!
Are says the seller 99.9% of owners use locking wheel bolts, took him 24 hours to come up with that answer and I would dispute that percentage and that means every time you fit new wheels to your new car you have to provide the new locking wheel bolts because you haven't got spares, to remove them from the car you are selling.
Take great care things aren't always what they seem and it does pay to question the seller before placing your bid or order.
Purchasing bolts to fit manufacturers wheels is not easy, even if you can find the manufacturer marked on the wheels?
Mercedes Benz, yes, But they will only fit Mercedes Wheels, you may be out of luck with some wheel manufacturers /retailers who will only want to sell you the complete package of wheels and bolts.
Using wheels of different Diameter (ie. spare wheel)
What are the consequences of using different size wheels to that fitted as standard on your model of car .
Some W168 models come with sixteen inch wheels, which will fit any W168 model, However there are up and downs to fitting these on your car .
The up side on my car was that the sixteen inch MB wheels fitted corrected the long standing -3MPH at 70MPH speed error.
I was always aware the car's speedo was reading just above the true speed. However when I fitted the 16" wheels this was corrected.
Down side, unless you make provision and carry a 16" spare wheel (or same size wheel as fitted on the car) problems will arise when you need to use the spare wheel, as happened to me recently despite the tyres fitted being in good condition.
1. First the ABS/ESP lamps light, if you go above 25MPH.
After these light had shown for approx 20 mins the Engine management light lit, and I'm also of the opinion that the throttle was not so responsive. .
I was aware the ESP/ABS lamp would light because the spare 15" wheel was turning faster, and the ESP system will pick this up .
However I was confused when having driven for approx 20 mins the engine management light came on.
When I did the diagnostics test on arriving home I found I had two fault codes:- PO 500:- Generic Vehicle speed sensor A malfunction. This was expected.
The second fault code being PO 420:- Generic Catalytic Efficiency below threshold Bank 1. I deleted this code, had the tyre punctured tyre replaced and re-fitted the 16" wheel back on the car, PO 500 was corrected.
However the fault code remained on the ECU until I deleted it.
So be warned Diagnostics can help but they can also confuse the owner into believing there are more problems than there really are. my advise would be to note the codes then delete and check again to see which codes return, then deal with those codes.
These are some examples of wheel bolts, apart from the length the contact/securing shoulder on the bolts is different the two outside bolts are Mercedes-Benz aluminium wheel on the left and the shorter one on the right, Mercedes-Benz 'A' Class Steel wheel. However the two in the middle are off the 'Smart', you will note that the shoulder is totally different, square and less rounded. Note also the narrow contact /securing wear line which clearly indicates the bolts are incorrect for the wheels to which they have been fitted, minimum contact having been made to secure the wheel.
I would expect the wear band to be the full depth of the shoulder as is shown on one of my 'A' Class wheel bolts which clearly indicates it's a correct fit for the wheel, fitting snugly into the recess in the wheel ensuring it is fully secure
Surprisingly the MB bolts are not marked with the MB star as is normally the case with their parts.
On the Mercedes 'A' Class these bolts should be torqued up to 115-120Nm Max using a torque wrench.
Use of spare wheel
. If the need arises for you to Change your wheel whilst on the highway, ensure you protect yourself and others with you, Get your passengers to a safe location while you carry out the wheel change If there is a barrier then place your passengers behind for safety and for you own safety wear
High visibility clothing
and place your warning tri-angle so as to warn others of your presence,
If possible get the car to a safe place before attempting the change the wheel.
To slowly drive (hazard warning flashers ON) on a semi flat or flat tyre to a place of safety may cost you the price of a new tyre, to change your wheel in a dangerous spot could cost you your life.
Having got yourself and other occupants to a safe place remember if aluminium wheels are fitted to your car you will need to use the shorter bolts provided with your spare steel wheel.
And if you don't heed the above warnings
I made a stupid mistake when changing a wheel on Monday: I forgot to use the short wheel-bolts.
The long bolts went 'all the way in' up to a point where only the smooth shank was in contact with the female screw thread on the wheel hub - so 3 of the 5 bolts never got tight, as if I had stripped the threads.
(No idea why the other 2 did get tight!)
The only reason I had to change the wheel was because of another stupid mistake by the last tyre repairer: they put long valve stems on, so when I hit the kerb the stem got yanked off... so I got an avoidable flat tyre!
I ended up taking the car to a tyre shop hoping they'd sort it all out. They couldn't deal with the bolts, so it had to go to an independent garage who had to cut the steel spare wheel away so they could access the bolts to properly cut the heads off, and then drive the bolts all the way through the hub before re-threading it.
Fortunately they saved the hub and it "only" cost me £160 including a new steel wheel. Jason
Jason thank you for being honest enough to tell us of your misfortune, just one of the disadvantages of aluminium wheels which are of course a MUST HAVE. Ouch If that isn't a fair warning then I don't know what is!
Tyre pressures are very important and yet tend to get forgotten. there is no excuse as unusually there is readily available information for the pressures of the tyres on the inside of the fuel filler flap. The information also includes details for hot tyres, and loading. It should also be remembered that tyre pressures are also affected by extreme cold and pressures taken may be slightly less than was expected. Make an allowance for this and try to check your tyres when the weather is normal conditions, what ever that is in the UK. In Countries where the weather is hot! Take the hot conditions into account as indicated in the guidance.
If you as a DIY car enthusiast haven't yet acquired a compressor then you can always purchase a small hand held digital pressure gauge, these are very accurate and are not expensive. word of caution make sure you are reading in either bars, or lbs per sq inch,
(1 bar = 14.5 psi)
(1 atmosphere = 14.7 psi)at sea level.
hence the difference in the pressures.
If you haven't got to the stage of a garage compressor then a portable compressor always makes a useful addition to your tools . This one a made by 'Michelin' runs on the 12 volt supply from your supply socket in the car (12volt Cigarette lighter) and is carried in a very neat hold-all bag which can easily stowed in the spare wheel compartment.
When purchasing new tyres you will almost certainly be given a wide choice of tread pattern which only you and your tyre supplier can decide on your tyre size
will depend on the size of your wheels, the size of the tyres fitted to your car can be obtained from the tyre wall(side)the price you opt to pay will also have a bearing on the type of tyre provided. In the case of tyre sizes we have a mish-mash of metric and imperial measurements the 195 & 50 which are in metric mille-meters indicates the width of the tyre and the profile which in the case of this tyre is 50% the 15 which is imperial denotes the wheel size. The 82 followed by a letter in my case T & V two of each which is shown with the other figures, indicates the load rating, and the letter indicates the speed rating both rating figures have to be obtained from tables.
If attempting to fit tyres yourself note that on most tyres there is a direction of travel and that following fitting, balancing is required if the best is to be got from a tyre
(balancing the wheel applying the wheel and newly fitted tyre to a specialist machine that determines if the wheel and tyre are balanced, the wheel is spun by the machine and the centrifugal force measured, weights are then affixed two the outer and sometimes the inner edge of the wheel to balance the combined wheel and tyre. The weights needed are shown on a digital readout on the machine. The tyre's life will be dramatically reduced if weights are required and not fitted, or lost, this will invariably show in the uneven wear of the tyre tread and in extreme cases can cause vibration to varying degrees.)
this necessary action puts tyre fitting these days beyond the average DIY enthusiast.
Having photographed this tyre, very slight defects in the form of splits can be seen in the tyre wall, these are almost certainly caused by curbing the tyre and will shorten the life of the tyre.
And don't forget to replace the valve caps, they prevent road muck from entering the valve stem,
Avoid the aluminium caps as they tend to weld themselves to the brass of the valve stem making them very difficult if not impossible to get off with damaging the rubber valve stem..
These are stainless steel with a brass threaded inserts complete with 'O' ring seals and are a top quality product, and are available off e-bay (see e-bay Mercedes)
So you ask how long do they last? 12 months at the most !! Oh no they don't fall off, the kids nick-up, two sets and I have one left!!
So we have to beat them at their own game, these caps now fitted lock onto the valve stem using a special key provided the outer aluminium barrel spins on the plastic cap making it more difficult to remove them without the key, I nearly said imposable but that would just be tempting fate. Not cheap but available on e-bay
However remember to carry the key into the car, or you will have to locate a child to remove them!!
Remember your life and the lives of others depend on the condition of your tyres, keep an eye on the depth of tread by using a tyre tread depth gauge marked TGD 1.6 easily obtained from good care accessories shops. Minimum tread depth, 1.6mm of tread must be present across three quarters of the breath of the tyre + and in a continuous band around the circumference of the tyre. The walls of the tyre must not show any form of defect, i.e. bulges which indicate weakness or sever abrasions, deep cuts or other damage. Tyres that show uneven wear, i.e. severally rounded corners or scuffing of the tread should prompt the owner to have the tracking checked and in the case of scuffing of the tyre tread the alignment checked. Both of these tasks can be undertaken by a a professional tyres fitting Company One such Company in my area is
Please visit this companies web site which is very informative. Time well spent and you may save your tyres from being exposed to unnecessary wear.
But why pay more when you could pay less and get a better all round deal?
Well that is precisely what I did today 01/11/12. Having had the misfortune of ruining a good tyre on our appalling Roads in Sussex, I visited
'Kenvad Tyres Worthing Sussex. who fitted me a New tyre for less than I have paid previously and the tyre is guaranteed against punctures and accidental damage.
Yes if I have a puncture they will repair it free.
If I accidentally damage the tire beyond Repair they will replace the tire and I only have to pay for the tread I have used used down to the minimum of 2mm.
With the state of our roads, pot holes filled with water, that sounds like a good deal which I have taken up.
The make of the tyre fitted is a NEXAN, check with your tyre supplier see if they offer a similar deal.
What have you to loose, or if you live local to Worthing Sussex, Phone Kenvad Discount Motorist Centre for a quote on 01903 238808/212920, where I received excellent service.
Tyre Tread Depth Gauge Use The depth gauge is placed at various points across the width of the tyre, as well as around the circumference, bearing mind that tyres do not always wear evenly, skidding and badly worn shock absorbers can play havoc with tyre tread and leave flat spots on the tyre. For more details on tyre care go to :-
http://www.dunloptyres.co.uk/site/tyres/car/tyreCare/ Using the Tread Depth Gauge
The sliding section a is pushed down allowing the gauge needle to measure the tread of the tyre, the green shoe forming a platform on the surface of the tyre. The measurement in millimetres is taken at point b rotating the gauge will reveal the precise depth of the remaining tread. The gauge in example is reading 12mm. The tread depth on a brand new 'A' Class spare tyre is 6mm, remember this gauge can used for commercials as well!
Tyres on cars do a fantastic job, however like everything else they do need inspecting and servicing from time to time, sharp flints can do untold damage to tyres unless removed, the example you can see is causing uneven tyre wear and scuffing around the flint, it is easily removed with a suitable tool, I have an old screw driver which I ground down to do the job. Nails and sharp objects on the other hand if spotted are best left until you get the the tyre depot of garage, either way it is to dangerous to change wheels unnecessarily on the roadside. The foreign body can be used as a marker by the tyre repairer, so do not remove it unless you are confident that you will not allow air to escape from the tyre casing. The alternative is to mark the wall of the tyre with a yellow crayon or suitable marker, before pulling the offending object out.
This photograph really emphasizes the need for good tyre care. Having just returned from Scotland covering some 1700 miles, I decided to check round the car, I was surprised and alarmed to say the least when I discovered not only a nail
in the O/S rear tyre but also a bulge!
On the inside wall of the the tyre as well.
Needless to say it has been replaced but my reward is that I wasn't involved in an accident involving others, caused by my possible blow out! When checking your tyres and having chocked the other wheels its worth jacking up each wheel so that you can spin the wheel, checking not only for embedded foreign bodies but splits bulges and alike, only then do you know that your tyres are safe to do the speeds of modern cars safely.
There is no doubt that a good set of wheels makes the car , however so do the centre hub caps , in this case a silver MB logo on a Black carbon fibra disc , which matches the carbon fibra fitted to the 'B' Post of the car.
In this case they are fitted to my 16" five spoke Mercedes Wheels, which incidentally corrected the 3 MPH deficit that was experienced with the standard 15" wheels.
So my question is was the speedo on the A class set up for 16" wheels as are fitted to the Adantgarde model as standard on the W168.
I like them better than the standard silver on silver and they are available from 'Diversty e Trade Ltd', on Amazon or e-bay for a little £14.99 including postage.
Many of neglect to check the pressure on our spare wheel until it's to late! when you need the spare it's preferable if it has air and that it's at the correct pressure or slightly higher so that you can place it on either front or rear. When replacing the spare back in the car , make sure it's stowed away correctly or you will be looking for the rumbles from the back end over the next week.
Make the most of the space in your spare wheel
there is sufficient room for two layers of tools and accessories, covered with a
cloth the items are retained clean & ready for use as well as rattle free.
Note the warning triangle A
which with other items is required if you are going
Be aware if looking for wheels for your A class that there are now two 'A' class models The W168 1998-2004/5 and the W168 200/5 0nwards
Various wheels are sold for the 'A' Class without specifying which model they fit so are they the same ?
The W168 has M12 1.5 bolts and the W169 has M14 1,5 bolts these are also for sale on E-bay as indeed are the wheels with few details simply saying will fit A class, although this is true they will not fit both W168 and W169 so take care when purchasing or you will be left with wheels that will not be suitable for your model of 'A' Class.
Bolts. The Mercedes Bolt has a distinct ball shaped neck where as most aftermarket wheels have a tapered next, buy the bolts from the maker of your wheels.
Mercedes Benz W169 Aluminium wheels are secured by the same bolts as the steels wheels so you do not have to purchase new bolts.
Where as the W168 Aluminium wheels require a longer bolt, again buy the bolts with the wheels to be sure of the correct fit.
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