[DavidD]

I cannot answer that directly but Mercedes had some really bad quality control issues from the mid 90's to around 2003-4, the accounts responsible for that were sacked and control handed back to the engineers again. The Mercs I have owned from 2005 onwards are much better.... The worst one I had was a 2003 eclass, that was such a disaster that the company I worked for insisted they take it back which they did.

 

[Slik hot]

I think the problem is that the roof drains come out just above the subframe ,and the water enters the subframe internally by the two holes at the top of the subframe,the new subframe still has the pointless holes

You can see the damp mark on the old one .it seems they use the subframe as a water channel, but I think we all know what happens!

 

[Sneaky Pete]

Does anyone know if the subframe design problem was solved during the life of the R171? Do the post 2008 facelift models have exactly the same subframe as the earlier years? Is it just taking longer for the later MY problems to emerge?

Does anyone know if the subframe design problem was solved during the life of the R171? Do the post 2008 facelift models have exactly the same subframe as the earlier years? Is it just taking longer for the later MY problems to emerge?

I am afraid not. And it is not only R171. Other models have the same problem,e.g W204 and W212. Even from later years like 2010. Seems more a design flaw in the subframes,allowing water to get in as said by @Slik hot .

 

[peterkw]

I am afraid not. And it is not only R171. Other models have the same problem,e.g W204 and W212. Even from later years like 2010. Seems more a design flaw in the subframes,allowing water to get in as said by @Slik hot .

Thanks for that clarification. I was thinking about buying an SLK 350 facelift but if the subframe problem is unresolved and MB are sometimes but not always covering the replacement cost, I will stick with my 54MY with a brand new, fitted and paid for by MB, sub frame. Otherwise I would have to drive around until the subframe is dangerous before I can take it in and hope for their good will again.

 

[Delucas]

Inferior Quality Metals used across the Mercedes Benz range R 171 / W204 etc and not helping of uk Rain / salted roads its also it dont help the rear axle chassis is open to the elements and the front chassis is closed off with Plastic panels which aid / protects from the Rain / salting etc .
Simply put Mercedes are not the Quality Build they once were many years ago .
Nothing to do with drain holes .

 

[Slik hot]

🤐

 

[paulthurlow]

My advice based on reading about other cases and my own experience is to contact a MB main dealer near to you. Let them know that you have a problem with the rear of your car that has failed (maybe not mention subframe at this stage) and book to have it brought in for them to 'take a look and see what is wrong'. When you take it in be very calm and describe what happened to you when you were driving along. You might want to have to hand whatever service record you possess. Then expect a call from them when they have taken a look and see what they say. Based on my experience they will let you know that they are contacting MB in Milton Keynes to see if they will take over some of the cost. Then wait to see if they confirm that MB will cover all of the cost. Take it from there. Try to keep it informal. They don't seem to want to commit much to paper.

Thanks for the advice. So I contacted MB UK via chat and was given a number for customer service and gave them a call. I explained the situation and was put in touch with my local dealer service department. Basically was told to book in for a visual health check. Confirmed subframe failure due to it being rotten. Spoke to service who submitted a “goodwill” request which was rejected. I explained my disappointment that others had their subframes replaced free of charge thereby setting a precedent and suggested that instead of submitting an electronic request that they might actually speak to someone at MB UK. Credit to MB Shrewsbury they went in to bat for me and after much to-ing and fro-ing via emails, reports and photos I was contacted next day with the news that they would replace FOC. What a result! My car is currently having the work done. Have taken the opportunity to replace the brake lines while it’s off. Many thanks to you Peter and everyone else who has given advice. It pays to persevere. Happy days😀

 

[Windinmyhair]

Brilliant. Firm and reasonable can pay off.
No consolation to those who have paid to have this done but another one notched up on the side of precedent.

 

[peterkw]

Paul, I am glad that it worked out for you as well. For anyone else with the same issue, remember that the MB dealer is your ally. If the work is approved by MBUK as 'goodwill', the dealer gets paid in full by MBUK. Even though it seems that MBUK are now willing to pay, it is a shame that customers have to drive around in the car until it becomes dangerous for them to replace the part. As and when there are more precedents, it may even be worthwhile for people to ask the MOT tester to pay special attention to the subframe. Currently it seems that many testers simply don't look there. A mixed blessing. Maybe the best would be to catch the rust when it is an advisory and then go to the dealer on the basis of that.

 

[paulthurlow]

Paul, I am glad that it worked out for you as well. For anyone else with the same issue, remember that the MB dealer is your ally. If the work is approved by MBUK as 'goodwill', the dealer gets paid in full by MBUK. Even though it seems that MBUK are now willing to pay, it is a shame that customers have to drive around in the car until it becomes dangerous for them to replace the part. As and when there are more precedents, it may even be worthwhile for people to ask the MOT tester to pay special attention to the subframe. Currently it seems that many testers simply don't look there. A mixed blessing. Maybe the best would be to catch the rust when it is an advisory and then go to the dealer on the basis of that.

Hear hear 👍

 

[peterkw]

Just as an encouragement to fellow sufferers, I post the pictures of before and after the replacement of the subframe. Slightly off topic, but I also include the photos of the balancer shaft test that I carried out recently. Happy. Now I can begin to enjoy my 54 plate 350 with fresh MOT as well.

 

[Trev5]

While researching Anti-corrosion spray's like ACF-50 to protect the underside of our cars, found this interesting You-Tube video:

Though standard ACF-50 did perform that well in the above test, though does attract less grit, they do do a Car version:
Link:

Corrosion Block - Keep your car Corrosion free

 

[Slik hot]

Wow!
I thought my frame was bad

 

[Sneaky Pete]

Just a heads up,I am now reading reports in the Dutch MB forum of owners that are proactively contacted by the Dutch MB organization to have their subframe checked at the dealer,free of charge, and if necessary replaced,also free of charge. Also for older cars,e.g. a W204 from 2008.
Don't know if this is only valid for MBNL or a change of policy for MB worldwide. Maybe someone at MB's legal department in Stuttgart had a wake-up call.......
Anyway,for those who encounter this problem,it might pay to persevere as stated by others. Don't take no for an answer right away.

 

[Avel Du]

If any members in other countries come across information (subframe) about MB recalling, or honouring replacements, please add to this thread.

My understanding of UK market is a mixed response.
Some had no issue with replacement. Others had to fight for it & many had no joy at all.
A lot depends on the MB dealer that you use by the look of it.
That in mind, I suggest checking our our recommended list for MB dealers in your location/country.

 

[peterkw]

As reported previously, I had an easy ride and willing service from Lookers Mercedes Benz in Tonbridge, Kent when they replaced my subframe with no charge after contacting MBUK. Lookers is present nationwide. I don't know they have a national policy or just a helpful head of service in Tonbridge.

 

[trilbies]

Arnold Clark Perth just replaced my 2005 SLK 200 subframe FOC. no questions asked....

 

[_bigglesworth_]

Just had a service from an MB specialist...... dreaded subframe rot. After reading here, I've just spoken to Mercedes main dealer in Bristol. Got a price for a rear subframe of £812 (parts only!!). Spoke to the parts man for a while, he said that MB can and have replaced subframes on SLK's of this age for free or will contribute to the cost. But it will be at their discretion and depend on the car and service history etc. Ownership is irrelevant. I'm booked in for a free 'visual' inspection in 2 weeks time. I will provide an update once I hear back!! Fingers crossed, they take pity on me and will do the works for freeeeee!

 

[peterkw]

Good luck. Remember that the main dealer is on your side. If MBUK agree then they pay the main dealer to carry out the work. If not, chances are you will take it back to your specialist... It shouldn't depend on the service history as this was not an item included in the maintenance or inspection schedules until 2018. Mine was well looked after but not with main dealer once warrantee period was over (in 2007!!)

 

[cherod]

Quite reassuring that so many main dealers are prepared to help 👍