In 2010 S550 4matic, transmission mode always defaults to "C" mode when restarting car. If the mode is set to "S" either in Park or while driving, car will not retain the "S" mode setting if engine is shut down. Car will always start in "C". Is this correct for 2010? Is outside temperature a factor?

 

It's normal.

 

Not sure about that - maybe on 2010's - my 2009 remembers the mode I left it in.

 

yes man it is normal and I hate thst too..

 

Yup, the 2010 E class does it too.

Kind of stupid in my opinion.

 

It was a change for model year 2010, probably has something to do with CAFE....

 

yea U R rite.

 

I had the 2007 S550, and when I picked up the 2010 S550, the transmission defaults back to "C" mode after you turn off the engine. Didn't like it, but after driving for a month, I found out that the "S" mode behaves differently from the previous generation (2007). I find the "S" holding on the gears longer and more aggressive. Slight pressure on the gas pedal will downshift the gears. Definitively more aggressive than previous version. I think that's the reason why the gear defaults to "C" mode now and to save gas.