I also have an 07 E63 AMG i never knew about having to break-in the car so i would drove aggressively including accelerate to 140mph and also hitting full acceleration at leat 25 times. I just found out a week later that i would need to break-in the car. My car also slams my head back during accelleration when brand new, but after 850miles of driving aggressively including full accelleration at least 25times and speeds up to 140mph, now the car seems to have lost alot of power and slower than when it was brand new. So would someone please help me out with this?

 

Johnny, I have a couple thousand miles on my E63 now and haven't noticed any power loss... and I broke it in HARD (accelleration wise, at least ~ never hit more than 110mph). The "break it in softly approach" is not doable from my perspective; especially on a powerful car like this. Let me explain; if you think about it, unless you picked it up straight off the boat, it's been test driven by at least a few people who punched it during the test drive to see what it's made of (I know I did, but with a different E63 at another dealership). So even if you treated it with kitty gloves during the "break-in" period, it's much too late cause someone else's already floored it ahead of you...

Personally, I believe in the "break it in hard" approach ~ whether it be my motorcycle, dirt bike, sports car, or 4x4 truck. I Have NEVER had problems with this approach! The fact is, the piston rings NEED to be expanded and seated against the cylinder walls properly in order to seal in the expanding gases for maximum compression. One sign of improper piston ring seal is the gradual loss of engine oil level; you should look into that if you feel you've lost power.

Again, this is my opinion based on my own experiences... I'm sure some people will believe otherwise.

 

I am also new here and looking to get either an M5 or a E63. Are you E63 guys happy with your cars?

Also, what is the difference between the CLS63 and the E63. Why would one choose one over the other.

Thanks
JimJ

 

I'm very happy with my E63. My only complaint is that it feels heavy (compared to my BMW 545i). Other than that, it's very plush and comfortable to drive but also very fast and agile whenever you need it to be; a good compromise between performance and luxury.