Is the corrosion on the rear springs indicative of an impending failure?

[Bedelon]

I just acquired an ML 350 a few weeks ago, which had only a few weeks left on its MOT. Upon inspection, it seemed to me that it would easily pass the MOT without any issues. Regrettably, the statement is incorrect.

Seeking guidance with the rear spring failure in my vehicle. I’ve just looked under the back of vehicle and visually they appear good to me….yes there is a fair deal of surface rust, but can you fail a mot on rusted springs? The coil spring has experienced a fracture or breakage according to section 5.3.1.(b) i.

Dealers ask £300 for a set of springs. The cost of labour is £180 per hour. The price of x4 is really high.
Independent are quoted £465 to install 2 genuine merc rear springs…Although not too irrational, it does make sense to some extent. Labour £70 ph…..If they are able to do the task in half the duration of the dealer, which is twice as fast, will I get authentic springs?I remain unconvinced.

Secondly is a problem with the front bearing - failure for excessive play 5.1.3.(a) Everywhere I search, whether it is on forums or online platforms, I come across a method for tightening the bearing in order to minimise any looseness or play. Does the ML 350 4matic truly have this feature?

The price for replacing the front wheel bearing is £304, whereas the cost of the bearing alone is £78.80. Therefore, I presume they anticipate the labour to last around three hours.

Now strangely after dealing with the dealers they have given me a quote of £226.20 - which is the bearing with a new hub (it says the tech guy that both are necessary for the work in the handbook) so now wondering why the independent didn’t include the hub? Only the bearing...which I am uncertain whether it is the cause of the issue - particularly if I can slightly tighten it to successfully pass the MOT.

In addition to the fact that changing rear springs can be accomplished at home with no difficulty, resulting in some cost savings, if the independent mechanic is installing authentic Mercedes springs for £300, I have no reason to complain about the two hours of effort required to fit them.The amount is £465.

Regrettably, the same cannot be said for the bearing. It is not a task that can be readily accomplished inside the confines of one's house. One may find springs for sale on autodoc and Ebay at a discounted price compared to authentic Mercedes ones.Is the authentic product superior in quality? Is it necessary to do the hub installation simultaneously with the bearing?

Cheers

[MundeDas]

MB springs are individual to your particular car , the colour coding on the springs is dependant on items applied at the time of manufacture. The MD is the only source for acquiring the appropriate springs for the task.

In my opinion, the optimal choice would be to get original equipment manufacturer (OEM) springs directly from the dealer and install them at home. Prioritise adjusting the wheel bearing, if feasible. If not, remove the hub and have an independent mechanic install a new bearing. This approach should result in significant cost savings.

[Micobe]

Can you confirm that the springs are not broken? It would be atypical to attribute their failure just to surface corrosion, as you said.

Occasionally, they abruptly break and release a spiral. Not always simple to see unless you know what you’re looking for.

Have you spoken with the MOT facility on the cause of the failure?

[Sumoto]

MB refuses to repair the bearing since it likely does not appear as an individual component on their Electronic Parts Catalogue (EPC). MB dealers are technicians, not mechanics. They prioritise intuition above intellect. I find it unlikely that they would engage in the meticulous task of using a bearing puller and press, unlike a mechanic.
Acquire the springs from MB.
After removing the hub and bearing, your technician will proceed to replace the bearing with a new one. There are several locations that provide bearings. Ensure that he does not get an inexpensive one. FAG is a leading company.

[Adv3nture]

Uncertain about the specific car, I experienced front spring failures in both vehicles. In one of them, the failure was not immediately apparent during the initial inspection. The lower part of the spring had sheared off but remained approximately in its proper position. It was only when the mechanic lifted the car with a jack that he discovered half of a coil had sheared off from the bottom of the spring, which explained the sensation I felt while driving. He extracted the problematic loose fragment to demonstrate it to me, and thereafter exhibited the failing spring, clearly revealing the sheared region.

[engrol]

Calculate the cost of springs by using Autodoc's base pricing.

[Captiva]

My CLK had many instances of spring breakage prior to installing Eibach springs. Have had no issues after then.

[MagicPod]

One of the rear springs on my vehicle had around the final 30mm of its bottom section broken off. This damage was not easily visible or detectable by touch. The ride height of the vehicle did not vary much, but there was sometimes an audible noise as I pulled off my driveway.

I bought rear parts online, namely SACHS brand. However, I had difficulties in obtaining the front parts, since both Eibach in the UK and Germany advised me to contact MB (Mercedes-Benz). I exchanged my item and received authentic AMG Eibach OEM as a replacement.

The little remark above fails to convey the extensive investigation I conducted to ensure accuracy. Fortunately, the previous fronts retained most of their component numbers and the colour code is apparent, however the rears lack this information. It was evident that they had been substituted by a prior owner.

[Bedelon]

ok,thanks all 😁