zdkdeeier493

The past few months the car has jerking pretty significantly on downshifts into 1st gear. It only happens at very low speeds and RPM. For instance, if I am approaching a stop sign and shifting with the paddles or the gearshift, and I downshift into 1st at around 900/1000 RPM, the car will continue to roll for about a half second and then a fairly forceful "clack" will be felt and heard as the transmission drops into 1st.

Ive been running the ASP pulley for about a year now, and the car hasn't had this problem the entire time. Is it possible that the added boost from the pulley has taken a toll on my 1st?

Couple important notes: Acceleration in 1st gear is VERY jerky as that the car will take off and then once the blower kicks in there is a very strong jolt/surge in power. Also, if I have the car in sport mode, when coming to a full stop it does downshift into 1st, but the jerk is not noticable.

Any ideas? I really dont want to have to rip open my transmisson...

jangy

Sounds like your TQ converter may be going hairy. Sorry to say, but manual mode is just not made for that type of use. If you drive it like it is a manual, then it will wear on the system with time. You still under warranty, right?

mclarenm8d

This is why I recommend fresh tranny fluid and having the tranny adaptation reset. Should only cost you 2-3 hundred. If your technician gives you blank stares or questions why, you should find another technician.

The tranny computer can get extremely aggressive at applying the torque convertor lockup if it measures that there is slip. I drove my car a long time with the TC lockup disabled, when I had switched it back the impact of how the tranny computer was applying the lockup was insane due to where it adapted to. Basically, because my lockup was disabled for such a long time the tranny computer figured there was massive slip. This is why I am a believer in reseting the tranny adaptation.

My theory is that aggressive driving/mods for torque plus comfort mode is what brings this issue on. I'm also of the opinion that fresh tranny fluid would have solved the issue for a lot of cars that had trannies and TC's replaced. The coolant contamination issue being the exception.

zdkdeeier493

Thanks for the advice. Can the trans. adaptation be reset by using the ECU reset trick or possibly by disconnecting the battery? Either way I think I would like to get some new fluid just for peace of mind.

mclarenm8d

That's a good point, I found that I couldn't use the ECU reset trick or battery disconnect to resolve the tranny adaptation issue I was having. Doing an ECU reset will help somewhat, just didn't give me as good of a result as the tranny.

Thinking this over again, you could try the following in order of increasing costs/complexity:
1. Sneaky ECU reset
2. Tranny reset
3. Fluid (might as well change the filter as well)

My fluid was real dirty at 50K miles. So to your point about peace of mind, if one of these cars is older or if it is closing in on 50K miles new fluid would be good.

MARK CUMMINS

I Would have the trans checked for stored codes via the SDS

MB has a couple TSBs on the trans for hard downshift 2nd to 1st
Snap ring mod..Updated snap ring
Trans Valve body...Updated Trans Valve Body

If You need a Local (LA) Tech PM me

baldmike73

i too was having the hard downshift to 1st from 2nd in my 05 E500. I know it had the 7 speed tranny but it was a TCU problem. I would def take it in to the dealer if you have warranty left and have them run some diagnostics. On my old E (now gone) they actually found metal shavings in the case and had to replace the tranny as the gears are all tore up.

TopGun32

I had the same problem..
the car has been in the shop for 1 week now.

They are going to replace the transmission and the torque converter, the kompressor clutch and the radiator.

I lucked out that the tech Juan was able to drive the car with me and notice all the jerking from the trans, the chirp

another problem is the constant belt slip when the kompressor engages, maybe your belt has had it.

I'll scan in the service report once I get it.

zdkdeeier493

They're replacing your transmission Wow, this might be much more of a serious issue than I previously assumed.

Here's my main concern. I have an ASP pulley which Ive had for a while now. Do you think I should remove it before I take it anywhere? Its pretty stealth, and Im not sure if a tech would notice it unless he was looking for it. But then again, if its found, my claim is kaput.

jangy

If you don't know your tech, then take it off. It would be very easy to claim that the oversized pulley stressed the drivetrain. It may not be fully true, but they are related.

Better yet, find a cool tech or SA so you don't deal with this BS.

MB_Forever

The jerk from 2nd to 1st is very common on NEW mercedes with the 7G transmission. My E63 had the exact same problem and so as 3 other E63 I test drove. Fortunately, the problem is only software.

My tech at the local dealership (close friend) told me that when they scanned the transmission software, they found no "down-shift adaptation" at all from 2nd to 1st. And sure enough, after they adapted my the transmission, the car shifts very smoothly.

Take it to the dealer and have them "adapt" the car's down-shifts properly, and you'll be good to go....

MARK CUMMINS

What the Tech did was RESET Adaptations for the trans via the SDS
Did The Tech tell you to go and drive it hard to re learn the shifting style?

I Hope that will fix your problem.. Good Luck!

TopGun32

I have taken the car in a few times for repairs.. with ASP on.

No issues at all.

In fact, the first time they replaced by tensioner pulley and nothing was said to me.

The tech Juan from Peske is really good, but he knows the E55 has these common issues modified or not.

The chirp, the old radiators that leaked into the transmission, the torque converters that start acting up.

The reason he is replacing the trans, is mostly since I have an older radiator and probably found fluid.

I'll get the car this week, so I'll definately post the service report.

StealthAuto

Be careful with those Tranny's

TopGun32

quick update..

my transmission is on back order.. so wont' arrive until next.

If I receive my car by next Friday, it would have taken 3 weeks.

The only good thing, we got a Nissan Pathfinder to beat up (Enterprise Rent a car). I have a few projects and I need to haul some plants and sh*t for the plants.