AMGFANs

Recently I traveled from my city to another. It is a 5 hours driving with speed around 110 or 120 kms per hour. The way I reach the destination is smooth. I stoped at one rest area. It took me almost 5 hour and 30 mins. When I do my return, I feel the handling is completely different. I stepped on the gas and see the kms reach to 140, and I feel the car is shaking and the steering wheel are going left and right all the time, even when I hold my steering wheel really hard. The road is ok, nothing bumpy or rock stayed. I have no idea if my tire had problem. I stoped at one rest area and did a quick check up, everything looks fine. I pop up the hood and the engine bay looks fine as well. Then I went back on Highway, under 120 is very smooth, until 130, the problem cam back. I want to ask has anyone have similar experince on highway? There is also a "drowsiness detected" assist came up on my dash board, I have no idea how the car knows I am feeling sleepy . Or maybe I had 2 and half hour non-stop driving record?????. I haven't decided if I should go for a check up or is it just normal for highway experince?

rory breaker

Maybe one of the weights fell off your wheel causing it to go out of balance.

As for "drowsiness detected" this explains:

Fung63

if you were feeling sleepy, it means you aren't having enough fun in the C63. Drive it like you stole it!

Roswell

I agree with rory, it sounds like ur wheels lost balance if it only happens at high speed. Just have ur 4 wheels rebalance (or at least the 2 front).

It's nice to know our cars are equipped with attention assist.

forcefed6.4ford

Ditch the rim weights and get some poly beads to balance the tires.

Fung63

did you hit a curb or any truma to the wheels? My wife's GLK hit a curb one time and slightly dented a rim, that caused shaking at higher speeds.

easiest way to see this is have someone stand outside and watch your tires when you drive by. If one looks loose/wobbly, you have a problem

Paculdo

does all c63 have attention assist? or only in 2012?

AMGFANs

Thanks for the advise. I will go do a check up for my wheels see whats going on. The "Drowsiness detected" is kind new to me. I had drove a 08 GL model on highway with more than 4 hours driving without rest, and it never have this kind of assist.

CoolBDPhenom03

Get it rebalanced. If it's missing a weight, it's easy to replace. If it's dented, the shop should be able to tell you. I hit a nasty speed bump on California's crappy highways and there is apparently a dent not visible to the eye, but it wobbles on the balancing machine. They tried to counterweight it as best as possible, but I get a slight vibration around 65mph.

Harold1898

Rear wheel balance?