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722.6 Transmission issue!

1K views 3 replies 4 participants last post by  Check Codes 
#1 ·
My 1999 C230K is having shifting issues.
To describe the issues, there is complete smoothness shifting up and down when driving conservatively. However, if I put my foot in the floor and try to drive more aggressively, the car does not rev up and hesitates and mildly jolts (almost as if it doesn't know what to do at that point). In a nutshell, the transmission behaves funny only when I try to put more power down than usual.

Does that fact that there are only issues when trying to drive aggressively hint to a mechanical problem or electrical problem?

I have replaced the fluid, filter, and adaptor plug (which was leaking). I ripped out the passenger floorboard and took a look-see at the connection to the TCM. The connector from the gearbox is quite oiled-up. But there is little oild residue on the connector plugs. But the connector itself is drenched. Opened up the TCM and found ZERO evidence of oil.

Not sure what to do next, thank you all for your time. :)
 
#3 ·
My 2000 C230 is the same way. It will be a little better after a reset, but it reverts back in a couple of days.

The only thing I could think that would make it any better would be new solenoids, maybe the AMG blue-tops that are designed for speed. (aka "Speedshift".)

I haven't seen much information about this, but I've dug up a couple of posts from Jaguar, Porsche, and Chysler guys (with the 722.6) who've enjoyed making the change.

Sonnax makes a couple of kits for the valve body that can be installed without any reaming. I installed the pressure sleeve kit, and got a little impovement. They also make a kit for the torque converter lockup, to soften some of the shifts ("in certain situations"), but it is for late model valve bodies, and my 2000 car actually has a valve body from 1997 (!), so I couldn't use it.
 
#4 ·
OP: I'm assuming you changed that leaky connector?

Also, did you reset the transmission adaptations to default as G-AMG inquired? Easy, cheap, quick...
 
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