dr.skp.ortho

Hi there,

Just wondering if anyone of you who have driven/own the new s550/s500 have noticed that when changing gears from reverse to drive or neutral to drive that there is a slight jerk? Is this normal or part of the transmission "thunk" that was reported elsewhere? However the shifts whilst driving are seamless! Any ideas guys? Thanks.

akburton

I detect a little kick sometimes. I'm just assuming the transmission is still learing my driving pattern.

konigstiger

I mentioned this before: P-B-27.60/61c JAN06 Rough Shift Quality includes the 221. Rough 1-2, 3-2 and 2-1 gearshifts could be the cause of a specific gear not being fully adapted or there could be a mechanical cause as well.

Most common complaint on the newer transmissions (i.e.: E & CLS) is that, when cold, 1-2 shifts rough (noticeable whereas all other shifts are not). I’m told there will be a software update to solve this soon. How soon? That’s up to the EDAC depending on how many complaints they receive.

RJC

Why would MB release the 221 with this issue not resolved during 2007 production?

konigstiger

Get as much coin in the door upfront and worry about problems later? Possible vendor/supplier issue therefore exhausted what was on hand for the earliest builds? Isn’t this the norm for most manufacturers?

RJC

It certainly appears to be the case for MB...how sad for the consumer.

Kar don

i havent heard of any 7g downshift thunks issues for the 221 S

op355

I posted about tranny thunk while back ago.

Dealer did a few things on my car, and it got better, but still does it.

Car still only has about 1700miles so I am waiting to see if it goes away once damn tranny learns my driving pattern.

iLoveMyMB

I think most of you are misreading the first post (maybe)? This "thunk" doesnt happen while you're on the road. It's right after when you change from P -> D or D -> R, etc. Yes, I notice it as well. It's a big jerk when you change the gears while you're parked uphill/downhill. The first few times freaked me out a little bit, but I got used to it by now. I don't know if that happens to everyone as well.

edit: I read ur message dr.skp.ortho, and I do notice it on flat grounds as well. But it's not as big as when you're up/downhill

dr.skp.ortho

Thanks ilovemyMB
Yes its actually a thunk when changing from P to D or R to D etc, not when changing the forward driving gears. Thanks for the response!

Nevada Jack

I have not had any events with my S550 transmission. I had a major thunk on my S430 and had to have the valve control replaced and readapted. But the 550 is smooth as can be...even when I first start it and the engine is cold. I detect a slight hint (not a bump or thunk) sometimes that the gear has engaged when I shift into R or D but this to me is completely normal.

I will be alert for any odd noises but to this point (980 miles) it is perfect.

02S430

hi guys i have the same problem on my s430. i realized if you apply more pressure on the brake the thump with go away i think its just the tranny sliping it to gear. it worked for me

silberrosa

The thunk you are referring to happens in almost all cars. Here is how to avoid it. Step 1: When placing the vehicle in park, place you right foot on the brake (should already be there) and apply the parking brake prior to removing your right foot from the brake. This puts the weight of the vehicle on the parking brake, NOT the transmission. Step 2: When you later take the car out of park, first shift the transmission to D or R and THEN disengage the parking brake. This might sound complicated but it is very easy to get used to and is something I have done since I was first learning to drive in my grandfather's W116. This will eliminate the thunk.

For the 221, the parking brake takes care of step 2 as it will automoatically disengage when you apply the throttle in either Drive or Reverse.

Brav

I wouldnt count on the rough shifting to go away. My 7G has been like that since Nov. 03. Doesnt matter how many complaints, they "cant duplicate" the problem. The 1-2 isnt so bad but 3-2, 2-1 when coming to a slow stop is pathetic.

02S430

the easier way is just apply more pressure on the brake and it will reduce it to little or nothing all that work just to get in gear is alot to me it works for me thought there was something wrong also