C230 automatic transmission noise
 

I have a 2002 C230 coupe with an automatic transmission, it recently developed a whine in second and drive, the noise goes away in the other gears and when in overdrive. i think its the planetary gears since i had one transmission to fail already because of the planetary gears. My car has only 21,659 miles. should i have the planetary gears replaced before they get any worse, or should i put something like Lubegard in it and hope for the best?

change fluid and drive till it dies. Why would you replace something that isn't broken? My 722.6 is certainly quirky, but after 144k miles, it's still holding its torque. That's the non-technical answer

thanks will, i will take your advice and ride her till she dies. lol

You diagnosed the problem, planetary failure, why wait fix it, it will cost more$$$$$$$$$$ later.

the whine is the same
 

thanks steve, any thoughts on why this is the second transmission to suffer planetary failure on this car, the transmission and torque converter was changed. i take very good care of the car, it only has a little over 21 thousand. the mercedes dealership ran a test on it and claims there is nothing wrong. the problem, is i remember what happened to the last trans. and this time i will be paying for the replacement.

The original transmission had the same symptoms? So they say nothing is wrong, the only test I know is to drive the car. Does the whine change pitch when it shifts, what do you mean by a whine in “DRIVE”

C230 whine
 

the original automatic transmission had the same whine, the dealership said nothing was wrong, a week later the planetary gears exploded. what i mean by the replacement transmission having a whine in drive, i quess its fourth gear, just before it goes into overdrive, is it growls under acceleration like a standard does in reverse. thats the only sound i know to compare it to.

still going after a year
 

a year later,, the car is still going,, the auto, trans, still whines in drive?? stops when car shifts?? i still think there is a planetary gear design flaw.. i will keep driving it,,, and replace with another new trans.,,,when it fails.. or i will sell it cheap to the first person who makes a good offer..hopefully it is worth something, since it only has less than 22 thousand miles on it... i own seven cars,,car crazy,,,