Subframe recall for 1974 450SL

Greetings to all as a new member! As a fairly new, and second, owner of a 1974 450SL, I am playing "catch up" in completing repairs as this model has less than 20,000 miles after being stored for over 40 years. I've recently learned of the open subframe recall and that this car does have a small crack in the subframe. Following the recommendation of my independent MBZ mechanic, I've taken the car to a dealer who initially said that the campaign is active and that Mercedes would cover all replacements since they originally admitted the design flaw that can lead to a full loss of steering when the subframe drops. Now, though, after the dealer spoke to their national representative from Mercedes, they are saying that no subframes or reinforcements are available any longer and that there's nothing they can do for the car or to help in any other way. I have also contacted MB USA directly who have repeated the "Parts No Longer Available" response and I haven't heard back from Mercedes/Daimler Germany. I'm new to this whole endeavor and wondered if anyone has any suggestions for how I should handle the situation. The car was purchased new from a Mercedes dealer in Paris and fully federalized when transported to the US in 1974. This current situation leaves me with a car I can no longer drive safely or sell to another collector ethically.
Thank you so much for any assistance! I have joined a local Mercedes club and show the car periodically but also have been using it as a daily driver and want to ensure it's care and safety. Please also advise if this isn't the correct forum to post this request upon.

Hi Laura,

welcome here. I have attached some Information about the subframe recall you may need.
Sorry, I have this information in German language only.

The repairinstructions are in the pdf document

Hi Laura,

the reinforcement parts for your 450 SL are still available. Please take a closer look here . As far as I know, DTL will also ship these parts to the US.

It should not be the problem for you to get the repair instruction in the english version.

Best regards

Hi Laura,

welcome to Sternzeit-107 to a member from Oregon!

I also run a 450SL from 1973 without these support plates. I asked a very experienced Mercedes-Benz mechanic (obelix116 in our forum) what I should do about it and whether he is willing to install them on my car. However his clear advice was not to install them for following reasons:

1. If it has not torn in 44 years, why should it do now. And there are no signs of cracks in the fornt axle support
2. If he welds there now he inserts a lot of heat. Bearings and bushings around will surely suffer from that and he will need to replace them as well. When this instructions were created, that work was done on fairly new front support.

That is why I followed his advice and left it as it is. It might be that MB had some failure once and thus created such an instruction for liability reasons. My recommendation: Let someone check the strength of your front axle support and then decide.

Anyhow a 450SL with D-Jetronic is a very good choice. Congratulations from Dr-DJet. And have a llok at my D-Jetronic website as well!

Hi Laura,

unfortunately the instructions 33-605 linked by Marcel are not available in English, at least not on Startekinfo. Funny, they have a similiar name as our website. Sternzeit means Startime .

However you will find the whole US workshop manual for your car above in menu "107er manual". A difference for you is that you will not see all German posts in box "Latest posts" on the right. There I only collect English posts. However if you can read some German, you will find every forum under menu "Forum".

Why do I write all this? I wish to attract more English speaking users to our forum.

Hi,
the parts are available. I strongly recommend to put those parts in as it was an official recall of MB. You get more info on that on the Ozbenz forum.

Regards
Thomas

Hi,

no it has not been a recall (maybe in Autralia) but a service instruction. However I have seen many 8-cylinders of these years without reinfocement plates. My car was also always serviced at a MB garage. So if it had been really enforced by MB it would have been installed there. And if you read the service instruction carefully they warn of damages on bearings when welding on mounted front axle.

If you plan to remove and disassemble your front axle, add those reinforcements then. It is risky to install them with front axle mounted in the car.

My god,
does it matter, if it was a recall or a mandatory replacement? It's a safety issue, period. There was even an instruction, that those parts must not be welded in, when the slightest little capillary crack was there. The whole front frame had to be replaced then.
Thomas

Hi,

yes it matters and also your statement about slightest capillary crack is not correct.

Dies kann durchgeführt werden, wenn bereits Anrisse am Lagerbock bzw. Vorderachsträger festgestellt werden. Ist jedoch eine Verformung im Bereich Lagerbock-Vorderachträger vorhanden, Vorderachsträger erneuern.

translates into: Welding can even be done if there are cracks. However if there are already twists of axle support, don't do it any more.

My car was in two official Mercedes-Benz garages for service. Both did not do this welding or recommended not to do it. It was not an official safety recall, just a service instruction which could be done during normal maintenance. So why create such a panic now? You do not even run a 350/450 SL/C, I do. I do care for my own safety. But when professional MB service people recommend me that I am better off without, I do believe them.

OK, I give up. Of course you KNOW, that it is limited to the 350/450. And of course I have no idea of R107, how could I forget.

@TS: You see, you get the full truth here, nothing but the truth.
No wonder, why only the newbies and the FOV's still write here.
Thomas

Hi Laura,
the pictures Marcel posted a the ones I took when I reinforced my subframe.

My subframe cracked after roughly 170.000km when I was parking my car - suddenly a loud bang and lower control arm was torn of the frame.
My car is only a 280SL which was even never recalled or originally equipped with the reinforced subframe - it still broke...

A you can see on the pictures, I bought a used subframe, striped it down, sandblasted it and welded the brackets in. I would also not have dared to just weld them in with the fully equipped subframe still on the car.

But as you probably will have to replace the rubber bushings of the control arm some time, it may be the right time to do the reinforcement of the subframe.

Sören

Gentlemen,

as Laura reported "this car does have a small crack in the subframe", her car does have the issue. Anything further seems to be a problem in communication.
The car has the problem - parts are available. So next steps should be clear.

Best regards
Martin

Hi Martin,

correct, I have overread that Laura already has a crack in her subframe. In that case it is clearly advisable to disassemble the front axle. take it apart and then weld in those reinforcement plates. I apologize for having lead this discussion in the wrong direction to Laura and to Thomas.

I do not recommend to weld in those plates on an installed axle. It will create troubles on bearings.

...a little correction :
the plates can be weld in with the axle installed, only the lower wishbones should be taken out and/or have the bearings renewed...

Greets
Christian

Please allow me to take a moment to thank you all for the responses. I plan to print out the thread, follow the attachments and explore with Google translator since my high school German is a bit rusty!

The thread echos the same controversy as the North American forums....does one try the welded reinforcement plates once there is a crack, or do you then follow the recall recommendations of full subframe reinforcement? My hope was for Mercedes to assist with the latter as the recall states, or at least to provide instructions for a current repair, but this hope has been sorely disappointed.

I’m attending an older Mercedes maintenance event soon and hope to use a lift to see the subframe crack myself and to take a photo to understand exactly what the extent of the risk is.
It’s such a challenge to have to make these decisions without the support of the manufacturer, since I don’t want a wrong decision to make the safety situation even more compromised. I really care about this car as a beautiful example of design and history and had found great joy in its use.

With thanks and a hope to keep you all posted,

Laura

As one more quick price of information, my understanding is that Mercedes USA is telling owners that neither the reinforcement plates nor replacement subframes are available so I’m especially curious to continue an exploration of this issue to determine its accuracy.

Hi,
you have to order A 107 330 00 68 at the Mercedes Classic Center in Germany, ask your local Mercedes Dealer or the Classic Center in the USA to contact them...

Greets
Christian

Hi Laura,

the German service instruction in brief clearly states that you may weld even if there is a crack. Should the subframe already have changed its shape then you must replace it. As there is no new part available, you have to find a used one that hopefully is in better shape. Reinforcement plates are available through MB Classic Center as Obelix has stated or from a 3rd source DTL as linked above. DTL could be cheaper even incl. transport costs.

Greetings All,

Just as an update, I attended a MB tech event today with the local club and the independent mechanic raised the car on the lift so we all could see the subframe crack. I would estimate it’s just over 1” long. Attempted to load an image here of the crack circled.

We also lifted a club member’s car that had the reinforcement gussets welded in to compare the difference.

Even though the German service bulletin allows welding, I’ve decided to be conservative and the MB shop will start the search for a used, recall completed subframe. There a local chap with a large number of 107’s that he parts out so that may be a good resource.

I think this may be the final step in my goal to ensure the car is safe and runs well. Sadly, MB USA continues to refuse to assist in any way so I’m flying solo in completing the recall unless I decide to pursue legal counsel.

Thank you all again for your help. I was telling the club members today about the English section of this forum and how much assistance you have offered.

I found a good 350 (M116) subframe that already had the gussets welded in and will be fitting this when the engine comes out of my project car.

I have to say that outside of Europe this needs to be watched as I have bought and owned numerous W116 S class models that have also had small to huge cracks in the subframe both front and rear and I know of 3 others who have experienced the same.
Bear in mind these cars are 40 plus years old and weigh in around 2000 kg and run on roads often best described as Third world lol (Especially here in Australia).
I found that RH drive cars crack on the Left side and LH Drive cars on the Right or Curb side so this is well worth inspecting.

I also have a Kit here somewhere I bought 8 or so years ago and as illustrated its a gusset kit to strengthen the old design.

ANY welding done on Auto Structural components MUST be done professionally to achieve full penetration and to ensure that there isnt too much heat and that the filler used when adding Metal to the subframe is the correct type.

IF you get this wrong you accelerate any crystalline fractures and make the base metal fragile and brittle so this is something that must be done by a seasoned welder to ensure the original structural qualities of the sub frame are not compromised.

The replacement Sub frame I have will go in with a full front end rebuild using rubber components (Not nolothane or urethane)

The more you know!

Tony

Tony is right on target with his warning for owners to be more aware of this subframe situation. I’m surprised that so few US owners are aware of the risk and need for repair. I successfully found an intact subframe for gussets but then found another that was already recall compliant with the factory made reinforcements. The latter was installed in my car and the former is at my MB mechanic’s shop to see if another classic car owner ever has the same need and would like to purchase it.

Thanks again for all you help!

Thanks Laura, I know that when i was driving this SLC I was hitting corners hard and throwing the car around a fair bit, the SLC is fairly structurally solid but I felt slight body flex so Id hate to think of whats going on underneath the SL's.
BTW the front subframe out isnt a huge job and considering how tight it is to get to Steering box and exhaust components its got to come out sooner or later im sure.