ChatWithaNinja

So I've been driving for a few days and I have some questions.

When driving on the highway at speed, I notice the steering is a little floaty. When I do a casual merge it doesn't feel confident, but if I do a quick merge, its super sharp AFTER I get through the mushy zone where it feels like the rear end is playing catchup to the front.
Is this a characteristic of the car or just the alignment?

How could I tell if it has a tune on it?

If I floor the gas hard, there is a "click" feel in/under the pedal. Normal? Basically I can floor it until it stops and it does nothing (besides the acceleration, heh), but if I press a little harder it feels like a button gets pressed.

Thats all for the moment.

INS1GNIA

Push the sport mode button and see if that helps with steering not feeling as floaty.

No real way to check if it has a tune yourself, would have to take it to a shop. Or you can ask the previous owner if possible.

That "click" is the kickdown switch.

zcct04

I've had my car for a long time and never noticed that click before, but just tried and it is clearly there. I GUESS that it's a kickdown switch, but in most cases the car is kicking down long before the pedal gets to the floor.

Sport button is just for traction control, has nothing to do with steering or suspension, so unless you are I doubt that'll help.

I've never thought of this car as 'floaty'. Things to check - do you have matching tires front & rear? Are tire sizes at or close to spec? Are tire pressures at or close to spec (see fuel door)?

JimGnitecki

Car magazine road testers have commented on how GOOD the C63's steering is compared to other cars in the same segment.

And I myself, having owned a LOT of car over half a century, find my C63 to have about the most nimble and responsive steering I have ever had, and that includes owning 4 Corvettes. The only cars I have driven that were as good or better were Lotus sports cars.

It might be a good idea for you to have someone experienced with C63 driving specifically drive your car and let you know whether or not it feels right to him. There could be something wrong - or worn, since your car is an '09 model (you have not given the odometer mileage).

Jim G

Alex.currie44

I have a habit of buying Benz cars used anywhere from 10 months old to 13 yr old. My current ride I got last fall at just under 4 yr and 46000 km.
For my own piece of mind I have had the older used cars checked over completely by my tech.
That includes checking all belts, hoses, fluids, filters plugs etc.
If there is a solid record of service we check what is due or pending e.g some items were due at 48 months so they got done as part of this. I do not buy cars which do not come with a complete service record.
My 2001 SLK320 was 13 yr old and had the original plugs in it after 60000km.
Alignment of all 4 corners is critical on these cars.
My bill for all of this was around $2000 for parts and labour.
Money well spent.
No disrespect to any of the guys on these pages who have more years for experience with the W204 C63 than I and they are pretty good with help but you will get a lot of inputs but none of us have enough info on your situation to be doing anything other than guessing.
If you plan to keep the car for a while maybe some consideration for a stem to stern inspection and service is worth considering including this issue.
Just a thought!

Jasonoff

What tires do you have and what pressures?

ChatWithaNinja

All good advice, thanks!

Tires are super cheap. I'm pretty sure they were put on there because when the dealer got it they were bald.

Actually, the cheap tires could very well be the reason it floats. I'm planning on getting it looked over soon - specifically the alignment.

CarHopper

^If you have 2 different types of tires on the front and rear thats your problem. Basically guarantee that is your problem actually.

BLKROKT

And something crazy that I've just discovered recently, is that if your front tire pressures are above 65psi, then your car will definitely ride and handle a little funny. I know, it's crazy, but you should check that too.

Adi-Benz

It is a kickdown switch.

Floating is probably tires.

Carbon Dated

There's got to be a story here if you want to share.

BLKROKT

https://mbworld.org/forums/c63-amg-w...-pressure.html

julours

If your tires are good, make an alignment and the floaty feeling will disappear.
Had this issue before, MB shop had to use crash bolts to properly make the geometry. Then it's fixed

Alex.currie44

I think you mean camber bolts and yes, they must use new ones each time the car is realigned. They are a one time use item.

julours

Yes, we can also call them camber bolts or TS adjustment screw. Part number A 000 333 10 71

Vladds

Are you referring to specifically Mercedes, or is it a general statement?


I run these in my Subaru, did not see something about them being single use.

Mort

MB calls them a control arm bolt kit. Used for making small adjustment to the front camber or caster. Part # 000 333 10 71. As far as I know they are not single use

Tlnt60

Hey, I had the same feeling when I bought mine. See if you can search my post, but it basically came down to my spacers and tire pressure

ChatWithaNinja

Great info!

I'm pretty sure the tires do match front to rear, but I will double check at lunch.

I'll be sure to mention the camber bolts, adjustment screws, or control arm bolt kit when I take it in to have the alignment done.