Are you sure it's gears grinding and not the revlimiter? If I'm not mistaken, 6000 rpm is very close to the rev limit on the 550 and from my past experience, BMWs they tend to be a little slow responding on the tach dial. So while your tach may have been indicating just under redline it might have actually been at the limit.

I'm pretty smooth now, but there are times when I jerk a bit.

I have found that the more spirited my driving, the smoother and better I interact with the transmission. This is a good thing IMO. I'd rather have it set up for that kind of driving.

Though different than the bmw manuals, I actually like the g35/350z manual. The throws are not long and smooth like BMW, but rather short and somewhat notchy.

I agree that the more enthusiasticly you drive the better the transmission is! Its a horrible car to drive if you want to just roll around with passenger's though. I find pressing the DSC button briefly really helps to smooth things out though!

I can confirm this - I had my CDV replaced with a modified version, and it gives you that extra control in engaging the clutch that helps smooth out the 1->2 shift...

Sorry to ask, but what is the CDV?

Clutch Delay Valve... what you want to do is remove it.


see here for more info.
http://www.zeckhausen.com/CDV.htm

My 1 to 2 shift can be a bit jerky unless I am just easing along with shift to second at very low rpm. I do this if I have people with me. In the mid rpm range it tends to seem jerky. At all out pedal to the metal I expect it to jerk since you are dumping the clutch.

I have no grinding problems at all.

Does it affect the warranty if you remove the CDV?

I find that my friends 2003 Manual E-class drives smoother with clutch changes and even shifting than my E60 manual. I would very much prefer something similar or closely resembly SMG driving the E60 manual. But on reading the funtion of the CDV, i forsee early wear out of clutches. I'd rather stick with the factory fitted variant unless it can be proven otherwise that the enhanced CDV will actually give my clutch the same life as what the factory fit will... although i'd love to see an improvement in the future from BMW.

The CDV will actually increase wear on the clutch. By removing the CDV or putting in a modified one, the clutch itself should last a good deal longer.