jrcart

I think you are missing the point as to where the actual risk may be. The cabin is no less strong than any other BS, it's probably in theory stronger because the frame has been stiffened in the BS. The problem is with the load bearing weight on the rear axle and suspension components, should the rear axles or suspension components fail due to being overloaded or over stressed something could break and casue you to lose control of the vehicle putting EVERYBODY inside the vehicle at risk, not just the rear seat passangers....or at least that's what I take away from the warning sticker.

kent426

I understand there are risks with any modification, I am not denying that by any means. There is a whole host of legal issues that the modification may run in to in the case of an accident. But I will say that if your reasons above is partially hypocritical because you have severely increased the loading on your drive train by adding the extra HP. So essence, if you were to follow your own logic, your car should not be street driven as it puts the rest of us at risk.

ecampbell

What are you smoking and please give me some. If you go to someone like Kitchener who engineers the rear end for the seat fine. If on the other hand your just going to drop a rear sear and strap your kids in then no.

PJK

So I'll ask again, what do you think generates more rear axle loading:

Racing around a track at 185 mph;

Running down a 1/4 track in 10 seconds or less; or

Putting 120 lbs on a rear seat and driving down the highway at 65 mph?

With all due respect, I am not missing the point. Instead, for every question/point I raise, the response is not an answer to the question, but rather pointing to some other "issue".

One of the issues raised is thread was excessive rear axle loading caused by the added weight due to the rear seat. I asked a question about rear loading with the added weight versus in racing situations. I also asked about any weight limitations in the passenger cabin. Any suspension designer will tell you that the rear axle loading in a racing application is significantly greater than the static rear axle loading caused by the rear seat while driving on the street or highway. I thought this point was clear and indisputable. You even mention rear axle loading caused by additional down force.

Do you really think that the additional weight in the rear seat is going to cause the suspension to catastrophically fail on the street, but it can sustain repeated full throttle 10 second blasts down a track and all-out track racing?

Another issue repeatedly raised is thread was the frame buckling because of the added weight due to the rear seat. My response is, why would the cabin in the CLK63BS be more likely to buckle than any other CLK? I asked questions which I thought would make it clear that MB wouldn't redesign the passenger cabin to buckle. You even seem to agree that the CLK63BS is probably less likely to buckle than a regular CLK (despite the fact that you were the one that raised the issue to begin with).

To be honest, I have typed several responses which I never posted because I'm not sure how willing people are to reconsider their opinions. In fact, I was going to ignore this thread all together (which is one reason why I never posted pictures). I have been trying to address the points raised in this thread. I decided to try to ask simple questions which would hopefully cause people to reconsider the "problems" that were posted. I'm probably done with this thread at this point.

SMP

What's so hard to understand about this? Since when does drive line load has anything to do with weight load? The rear axle for the BS has a weight restriction, like rear passengers, luggage in the trunk or excessive down force generated with a huge wing.

SMP

Thai stick or pineapple express ... or just a low tolerance level for any kind of medication

PJK

Increased drive line load can result in increased weight transfer to the rear of the car, which results in increased weight load on the rear suspension.

PJK

And if we are going to continue to pick apart every word in this thread, then let's be accurate. The BS does not have a warning label about excessive weight load on the rear axle.

SMP

Don't think so .... nice try though. Drive line load does not add mass ... but whatever makes you feel better to justify your conversion is fine by me.

I could care less what you do with your car. Your car, your and your wife/kids life and safety. Personally, I would never install rear seats. I have a few other cars to haul people around.

SMP

I guess you never bothered reading the owners manual? Ever looked that the car is certified as a 2 seater, not a 4 seater? Like I said, whatever makes you feel better.

PJK

You really don't think that increased drive train load due to increased acceleration is going to cause a greater percentage of the overall vehicle weight to be transferred to the rear wheels???

I have multiple cars too, so what?

SMP

As much as I would have liked to, I never said it on a public forum, but you are a moron. Talking about picking posts apart. Let's look at yours: You compare someone taking their car to the track, whether it's a road course or a drag strip, which is in a controlled environment compared to public roads where you endanger innocent fellow motorists? You compare going down the FWY with someone wearing a helmet, a racing suit, having a 6 point harness and the car equipped with a roll bar on a racing circuit?

What did you expect from us? Why post this thread in the first place?

One more time, maybe this time you'll get it: Your car, your life, your wife's life, your kids life. Do whatever you want, but don't come on here justifying your moronic actions and expect all of us strapping on knee pads.

jrcart

I guess you could make an argument for that. Touche ...a weak argument, but an argument nonetheless.

PJK

Wow... I don't even know where to begin. In fact, forget it. You are not worth it. You refuse to address my points, and instead make this personal. I will answer one of your questions... I expect nothing from you.

SMP

Just to clarify ... I take this personal because there are innocent kids involved! I could care less about you, but I have a soft spot for kids.

PJK

Good job.

WTDoom

This is such a bizarre thread .

It's basically an entire forum ( and the vehicles manufacturer ) telling someone to be careful and that we care about what happens to him and or his passengers ( not to mention innocent bystanders ) and that person telling everyone ( again INCLUDING THE MANUFACTURER ! ) that he knows best and they should all take a running jump .

I think , OP its time to take a step back and read this thread again .

Only on the internet

wonsuk_utmb

I really feel like he is trying to convince himself that the rear seats are safe, although no one really knows. There is definitely risk involved but instead of acknowledging the risk, he's trying to debate them away.

jrcart

I suggest he take this conversation over to the AMG Private Lounge site and ask the question there. They used to even have live Q & A discussion sessions with engineers, then he could argue with the guys that designed and built the car.

ecampbell

He still wouldn't get it. As posted above, he didn't get the response he had hoped for and is now trying to justify what he has done to himself.

If something did happen and we was on the wrong end of a liability suit, he would look pretty silly trying to show he is smarter than MB and the warnings didn't really have to be adhered to. On the bright side, if he were to win, perhaps MB would hire him as a senior engineer.

OP, again your are completely missing the point of what we are trying to say.

kent426

I find this kinda funny that there are at least 3 others who have installed rear seats and I see that Ecambell and Jcrt have all had reasonably positive things to say. So why so negative on this thread.
And please about saving the children, there are a lot bigger evils than putting a rear seat in a BS, talk about obesity, lack of education, pollution or letting your kid ride in a pre y2k compact car.
Lets face it, I have a lifted Dodge truck with 35" tires and an ARB bull bar bumper, regardless of how safe you think a benz is, if my truck where to hit my C55 at a speed differential of over 45 mph, the benz occupants would be toast depending on where I hit it because the bumpers no longer align. Welcome to America, we modify everything here without major certifications compared to Europe.
I think the add of the rear seat from the CLK was a great feat.

wonsuk_utmb

The finepoint is the OP is trying to argue away the risks when that can't be done. Each time the rear seat install has been mentioned, the rear load came up in the thread. The inherent risks were brought up also. It's just a matter of acknowledging the risks. When it comes to modding to each their own, but there are risks to all the things added to the vehicle.

Traffic53

sorry to be a part of this train wreck, but it's just irresistible.

what kind of data will satisfy you fellas that the car can handle rear passengers just as the regular CLK? it's the same chassis. jeez. stop assuming that it's not there because of safety. the CLK 63 and the BS crash test with the same results under identical scenarios. quite obviously, the BS will corner, brake and accelerate at higher levels, which increases the likelihood of crashing at speeds greater than what the car needs to be certified at. bottom line, they don't trust people, so they eliminate the seat. the CLK 63 is not capable of some of the same tricks that the BS is. solution: don't drive like an idiot with the kids in the rear. i don't need this warning, as i understand and appreciate that a fast car can kill you and your occupants. but, it's just plain bull to think that a BS owner would be negligent by opting for the rear seat add-on. some of you are acting like you're safe from any injury by simply following manufacturer recommendations of wearing a seat belt. then- when you do get hurt in a crash, you'll be looking to sue mercedes benz. after all, you did your part.

talk of a weaker rear end is non-sense. sustained loads of 150lbs at legal speeds is zero compared to the loads generated by a car that can pull 1G on the skid pad. the rear axle and suspension are loaded at 2000# just sitting there. they are probably capable of supporting 6000# without a problem. you think 150# more is going to break the camels back? i know some of you want to think the car is not a CLK, but some sort of limited edition space craft. sorry, it's a CLK with some go-fast/stop-fast bits attached, which amounts to a brilliant CLK, for sure. but it has the same crash attributes as the CLK 63. that's the key. they are not stamping out special frames and chassis for the BS.

respectfully.

dragCLK

I read this thread, and I honestly do not understand why the additional weight of a rear seat will cause the rear end to catastrophically fail (as opposed to premature wear)?

Now I'm wondering if the additional weight of a roll cage is going to cause the rear end to fail. The rear seat probably doesn't weigh as much as a 10 pt. roll cage. Is the rear end really weak in these cars? I didn't think so.

As long as the gross axle weight rating isn't exceeded, shouldn't the rear end be okay?

SMP

Why this discussion is still on is beyond me ... especially from the experts that don't even own an CLK BS. It's stated in the MANUFACTURERS OWNERS MANUAL that the maximum luggage or whatever you'd like to carry in the trunk CANNOT EXEDE 110 POUNDS ... if you bother to look it up, it's on page 347.

This has NOTHING to do with the frame, but a redesigned rear axle specifically for the CLK63 BS.

The rear seats will weigh about 55lbs., plus seat belts and hardware. A couple of kids at 60lbs. each = about 180lbs., which is over the weight limit according to the ENGINEERS AT MERCEDES BENZ, CLEARLY STATED IN THE OWNERS MANUAL

Let me ask you this: Why would they print it in the owners manual?