W203E35

Waz up MBWorld bros,

First and foremost Happy New Year to everyone!!!

Lately when I put my car in Drive it Jerk forward very violently. Then when I put it in Reverse it again jerks the car but much more violently. Also recently when I put my car in drive it takes a lot of time for it to engage (3 seconds, before it was 1 second).

Do you guys believe the jerking would be from the transmission mounts? What do you guys believe the lag is from? I have not yet done my tranny fluid change (57k) so do you guys believe if I change my transmission oil lag will go away?

Also the gears sometimes upshifts too high of a gear. For example i'll be accelerating and when it's time to shift I feel it shift an extra gear leaving me well below 2k rpm (maybe even close to 1k...no joke) and it moves like a slug. Then when I press the pedal harder it will hit the right gear leaving me around low 2k rpm. Maybe I can fix this with DAS and adaptation but how about the jerking? Thanks

Ever since MB changed my valvebody I have felt the car turned into a whimp. Downshifts much later, upshift much quicker...car is always at the wrong gear

Thanks

LILBENZ230

My transmission mount is broken right now and there are no jerks at all. I also have yet to have the fluid changed and there is no funny behavior. The 7G always seemed to be in the wrong gear.

This doesn't sound good. Have you checked the fluid level?

laneshift

The jerking overcomes your brakes?! Or does it just feel like your car "wants" to go in said direction?

Forgive me if it is not the case, but is this another classic Karo joke? You almost had me with the airbag joke a while back.

W203E35

I can't agree more about the 7G always being in the wrong gear

Interesting that your broken tranny mount doesn't do this...so I guess my assumption was wrong.

No this time no Karo airbag joke

It just jolts forward but the car doesn't move. Then when I put it in R is jolts up.

cpbeasley

It's most likely the thinga majigger inside the bloopidy blah, incorrectly doing what I like to call a "karate chop" before finally leaving you with a jerky movement.

+1 for 6 speed

phister

I'd go back to MB and tell them ever since the valvebody change you're cars messing up and see if they'll do a inspection to see if they know whats causing it to do that. Did you do your tune before or after the valvebody change? Maybe they messed with your ecu and reset it.

W203E35

I have always had trouble with my transmission. It always use to jerk when I put it in gear. Originally when I mentioned this to my SA he said it's my transmission mounts. They changed it and it wasn't as bad. Now the problem is back again after 20k miles. I think I might first do the tranny oil change and see if that helps. I'm also thinking of hooking up DAS/SDS and doing the adaptations so it can adapt (for the gear skipping). After I started this thread I went for a drive and did a few good rips and now the transmission feels better. I came home and put it in Reverse and Drive and it doesn't jerk as much which is making me believe it might be my transmission oil

phister

hmmmm... maybe. You might be low on tranny oil. Might as well start with the basics and go from there.

Glyn M Ruck

Karo - isn't that transmission repair still under warranty. I would take it back & tell them to sort it out.

AdidasC230

is it only when cold? my parents cars jerk when you put them into gear because they are idling high at like 1500 rpms to warm up the cats...Also isnt the auto adaptive? Maybe its aggressive shifting into all gears because you drive it hard? Just a thought. MB told me all repairs carry a 6 month 6k mile warrantee on after OEM warrantee repairs. Did you check your trans mounts? Or your Fluid level, its pretty easy to do (well it is on a manual)

johnand

Karo, change your f-in transmission fluid and filter already. You are almost 20K overdue. Do that 1st, then report back. Or at least check the fluid level, but if you are going to go through that trouble, might as well do the service.

I still suspect you may have a collapsed transmission mount. The way you drive and the fact that you had a broken motor mount at one point, means your transmission mount is stressed. Even though Matt has had 2 collapsed mounts and no issues, doesn't mean you won't. Your car is a different animal than Matt's.

Also, if you are bored, post the current adaptation values here for both upshifts and downshifts. I wrote mine down before I did my 2nd transmission service, then reset them and rechecked them a few week later, and the values improved a bit.

W203E35

Thanks for the replies guys.

Glyn, It's been over a year since the tranny repair so I don't think they'll cover it.

Adidas, I haven't checked the transmount or oil level but I did determine this happens when the weather is cold.

Phister and John, you guys are right I'm just going to go ahead and change the oil. I'll refer to John's Win thread and go from there.

Thanks everyone!!!

Glyn M Ruck

Please listen to John

OneOfaKindTrini

My car bucks a bit now and then when I put it in drive. No other drivetrain issues such as you Karo. Maybe someone knows what really happening.

Xhale707

My car had the same issues when the fluid in my car was black / green ATF fluid that is. But mine only had the issue when i would put it in reverse it would take 3 secs or so to engage. And it doing that was rare 1-40 times. But my car would jerk from park to Drive or park to reverse.

If you have a dipstick check the color & level if not look under ur car check for leaks around the transmission pan / plug area.

I would just go get your atf changed

splinter

Appeal to you Service Advisor’s sensibilities in this instance, Karo. He ought to make you whole.

Drove behind a fresh M272/722.9 combination during the holiday lull. Smooth as melted butter during each drive cycle.
That I manually selected the appropriate multiplication ratio for its various load vs. speed and acceleration/deceleration needs should rightly be considered hearsay.


Hope yours doesn’t look like Xhale707’s DIY servicing upon inspection.

csherm9999

This is an old thread, but I'm hoping the OP or someone else figured out why their car waited a few seconds before engaging when placed in drive. I'm having that problem and it's driving me crazy. Thanks.

johnhef

A little service history of your trans please? Year, model, how often changed and when the last change or flush was done etc etc

csherm9999

Hi Johnhef, It is a 2006 SLK55 with 100k miles. I just had a complete transmission service done on it (all fluids, etc.) and it didn't fix it. It also has this 3 second delay when going into reverse. Other than that, seems like it works well (just bought the car). It downshifts kind of abruptly when approaching a light occasionally, but I've read that that is common.

samaritrey

Who did the service? Proper fluids used and correct level? You have an early 722.9 7 speed which I know some had issues with the valve bodies but I don't remember what the symptoms were you may want to check that out.

johnhef

Early .9's also had that issue with the spring clip coming off and causing a rough 2-1 shift coming to a stop. I'd suggest taking it to a dealer or trans shop that knows this trans well for help.

ken samuel

my 2007 c280 jerks when moved into drive or reverse and gets stuck in first gear i really need help on this thanks.

Royal Music

Same thing happens to mine I have an 06 going to take it to a shop this week. I will let you know what they tell me. And does your S + C button work?

slammer111

Not sure if this applies to the 7 speed (I have a 5 speed), but check your fluid level, followed by that famous leaky pilot bushing. This was causing weird shifting. Sometimes my car even dropped out of gear on the highway.

I also once had a problem with the car slamming into gear when shifted into D or R during cold starts. Turned out to be a bad voltage regulator (attached to the alternator) which was making the various electronics behave strangely. My car also threw a few errors on the dash when that happened though.

johnand

What is your service history with the transmission? Getting stuck in gear is limp mode, and based on your model, is likely the infamous 722.9 conductor plate issue. You likely need to replace the valve body and have it coded.