Does anyone have an explanation on why our cars seem to engage reverse twice? What I mean is, when you put it in reverse, it will feel like it engages reverse, but if you press the gas, you still can't go anywhere. You have to wait another 2 seconds or so, then it will feel like it's engaging reverse again (slightly harder/louder than before) and you can then hit the gas and move backwards. I know it's not just mine that does this as Ive read about this before, but I didn't know if this was normal, or just a common issue with these cars.

Does anyone have a reasoning for why this does this, or just a theory, and is this normal, ie do these cars do this from the factory at 0 miles? This morning I went to back into a parking space, and I put it in reverse, felt the first "clunk" then waited a couple seconds longer, and felt nothing. I thought "okay, Ive been sitting here for a while (in reality maybe only 4-5 seconds) maybe I just missed it", so I hit the gas, and nothing, then it finally decided to grab mid rev and jerked backwards. This is quite annoying when trying to back up in a hurry.

This is absolutely normal. Patience is required. Do not accelerate until pressure normalisation.

You need to wait for transmission fluid pressure to normalise after electronically engaging reverse or drive & respective clutch pack lockup. Some of the delay is caused by the VB redirecting fluid & some by design in TCU programming. Benz designs latency into everything including switching on the HVAC. They want the cars to have a calm unhurried feel.

Glad to hear it's normal. I always wait until I feel it go into gear twice, but this morning it took a lot longer than normal and I hit the gas prematurely. Thanks for the explanation.

Yes there's a little delay when going from drive to reverse and reverse to drive, an automatic transmission is using hydrolic clutches that need a little delay, always fully stop and wait tranny to be engaged a few seconds before pressing the gaz pedal, this is normal, if you go from R to D while the car moves back and you accelerate the car will shake badly telling you you're doing wrong with the tranny, avoid it if you want to save your gearbox

Pascal

This phenomenon is super weird because every other car in my family doesn't suffer from it. 2007 S550? nope. 2008 335i? nope. 2002 S500? nope. 2009 C300? yes. but why only my car? The other cars are instantaneous. Do they not have the same pressure normalization?

Even though I repeatedly tell my mother not to, she will reverse and then without coming to full stop, stick her S550 into drive - Funny thing is, the switch is completely smooth and flawless. If I tried that in my C, I think my transmission might explode

I'm trying to understand why it's only OUR cars that have this problem. I understand that it's normal for our cars, but why not every other car? The benz thing I understand, they really do like putting a delay in everything. But what about the S550? or S500? Different class of vehicle so better quality transmission?

You are very knowledgable Glyn and I appreciate all your help, in this thread and the hundreds (or maybe thousands?) of other threads

The differences you are experiencing are all in the software loaded to the TCU. The transmissions are the same. All the transmissions suffer it to a greater or lesser degree. My 2009 CLK suffers the delay in the reverse & drive clutch pack lockup but does not suffer any kickdown delay etc. that other models like the W204 do. Benz applies different software mapping to different models.

AMG models have very different mapping & everything happens much more quickly with some loss of refinement. On the latest AMG Speedshift they have even done away with the TC & fitted a wet clutch.

We are talking electronics controlling hydraulics here & the TCU's can be programmed for different characteristics.

There is actually protection for what your mom is doing. One day she is going to overdo it and lose drive completely to protect the transmission. The only way to regain drive will be to switch off the car & restart to reboot the processor.

This protection was more sensitive in the 722.6 5 speed transmission.

This isn't normal..it's a common problem on the early 204 cars. There is a transmission software flash that fixes it. Visit your local MB dealer to have the trans. software updated.

Thanks for the explanation! That makes me wonder if it would be possible to flash the same software from the C63 to our Transmission. If I remember correctly, the transmissions are basically the same in the C63 and the C300?

Early C63's have the same transmission in a higher torque version. Later C63's have the newer Speedshift.

The only thing that might prevent flashing the AMG MAP to the TCU of a standard vehicle might be an unhappy marriage with the ECU.

My CLK has the very last 722.9 flash prior to introduction of the 722.9 Plus.

I bought my C with a simple fix already built-in, but alas, no longer available over here.

And what would that simple yet unavailable fix be?

Manual transmission!

Guess I walked into that one!

An Observation.

In the modern "instant " society it seems that many car buyers are not taking the "time" to fully study & test drive their proposed new rides.

There are lots of complaints about this ATM lag & other peculiarities of the MB mark that should have been picked up in a test drive or three.

My dealer allowed me to take the car home overnight so I could appraise it over a period of time & put it up on the ramps!!

It would help greatly if consumers understood the psychology of buying & selling eg by taking the heat out of the deal by doing sfa for 4 days.

You make a good point. Even in reasonably priced America a new car is a big chunk of cash. Proper research should be required. You are not buying a disposable razor.