C230K kickdown shifting problem

[BenzOnline]

Hi,

Occasionally when I use the kickdown on my 99 C230k, it gears down but the problem is, the rpm raises and then slams into the gear. It only done this a few times otherwise its perfect. No other problems and I did have the transmission fluid changed by MB, 2 months ago. The car has 60, 000miles.

What could be causing this delay and then slammed gearing?

[Michael K]

Start saving for some expensive 722.6 work. Ask me how I know.

[BenzOnline]

Explain me all the symptoms you've had with your 722.6 transmission. Im sure mine is still ok but we'll see.

The car is not driven too much...maybe thats an issue?

[Michael K]

Mine never did what you're describing. Rather it worked perfectly for 120,000 miles (fluid changed at 75k) and then died. I was moving at speed in fifth gear and pushed the accelerator to get fourth. It slammed into fourth and then stayed there the rest of my trip (limp home mode). Parked and came back later still in limp home mode but now only second gear. The tow was a couple hundred bucks plus (this is a guess) about $1,200 for my indie to replace (I think) the valve body and control module. It's worked fine since then.

From what I've been told you've done the right thing by changing the fluid. I'm not sure, and perhaps this is the real question here, but until it breaks, there's nothing else for you to do. Is yours under dealer-backed warranty?

You don't by chance feel like mailing me your MAS so I can test mine against a known good one do you?

[BenzOnline]

Nope nothing else I can do. Codes that came up when they did the fluid was "torque converter lock-up" but they said this wasnt major and something probably triggered it once and never again so it stores it. I dont know.

The MAS I just replaced...with a new one. I dont have another one.

[Michael K]

http://www.transmissionspecialty.com/parts/parts/68942-01.htm

[BenzOnline]

Yup looks like this will in time have to be replaced. I can still let it go for awhile though.

Thanks!