Would hard acceleration ruin or damage my transmission?
 

Hope it can handle all the abuse lol

Nah, it should take it. I would at least wait until everything reached operating temps before hammering on it. And keep up with the maintenance. Although not officially indicated, I strongly suggest regular transmission fluid and filter changes. I do it every 40K, but even every 80K would be good. I really abused my ML320 (on and off road) and it just kept on going. Actually, it's still going - a dealership mechanic bought it from the guy I sold it to and last I heard, it never had a single engine or transmission issue in almost 200K miles.

I have an old school thinking of this topic, not sure if this is a myth.

Your engine and transmission have to be used to the abuse If you baby your car for a long time and you do hard acceleration all of a sudden, this may cause some damage.

Like I said, not sure if this is a myth or not.

Seriously, I beat on my car like it's a rental. Im an expert on how hard you can get on the gas without engaging the TCS and I look forward to people who try to pass me in the gutter lane at red lights. It is a rare trip that I don't get a tire squeal or fully depress the gas pedal at least once. Freeways on-ramps are legal drag strips.

I changed my fluid at 38k (the car is at 41k now) and the trans is still ok. The only issue I can detect: If i manually shift the car into 1st from a dead stop or if the mode selector is in S and the car downshifts into 1st when coming to a stop there is a little bit of slop or a slight clunk, and it actually started doing it after the trans fluid change. Otherwise it works flawlessly.

Don't know how it will be at 60k or 80k though :nix:

Frank, the 722.9 will often clunk on downshift to 1st. There is new code the dealer can download that will help with that and make overall ****s much smoother. They would probably charge you an for an hour or maybe less to do the update. I think it's worth it. The only annoying thing is that after the update, even in S mode, it won't hold first gear unless you really stay on the accelerator, almost to the point of spinning the rear wheels. Of course it's easy enough to fix that by tapping the TouchShift to manually hold 1st gear.

The transmission is designed for you to try and destroy it everyday. As long as everything is warmed up and well maintained it will take whatever you throw at it all day long. Mercedes never want to see you for a ruined transmission, too much work.

Its not often I am at the front of the queue waiting for the lights but I always floor it every time I get the opportunity also.

Talking abusing transmission, any one had or heard about transmission vibration/ressonation in the rear while pulling hard?

My car does that for almost 3 years, and all engine mounts, gear-box mounts and new diff were installed, but still have that situation!

I checked everything I could, including rear bushings etc. and even made an unusual test, I removed my KW v2 and installed stock suspension and... much better! Then added some cement bags on the rear :naughty: to make weight and lower the rear... and again vibration!!!
What could I conclude with this... nothing, now one knows without removing the rear transmission!

What could that be? Any thoughts?
If that was normal, many of you guys with lowered cars should notice!

I also have that clunk on downshift to 1st since new!

PS: I have from stock 515Nm of torque, but now running 700Nm... CDI power! :zoom:

I had transmission failure on my 2003 at 30k. Dealer replaced with an entire new transmission shipped from Germany. Was told the tranny was an old design from the w208 and replaced with the newer 2004 trans. I drive my car pretty hard and will hit 200k sometime this fall. Just regular fluid changes.

These transmissions are robust. Especially the 5 speed if serviced every 39K miles 60K Km's. Other than Siemens conductor plate issues etc. on early 722.9's they will go a very long way.

The most common failure is the first to second one way clutch after just too many high torque changes & this shows itself in Taxi service, mainly behind diesels at mileages exceeding 600,000 Km's.

If you are running the latest software you should not get a clunk back to first gear when approaching a traffic light. The car comes to rest in second & then engages first so you don't have that massive 2nd/1st ratio change.

The most common cause of a clunk is clumsy driving when accelerating then braking hard. You catch out the Torque Converter clutch either locking up or unlocking.

Glyn is correct - the new code the dealer can flash will not allow a downshift from 2nd to 1st until the car has stopped, and that prevents the clunk. And it also makes overall shifting much smoother. I know we hate to visit the "stealer", but getting the latest TCU code flashed is well worth it. They should charge you about an hour of labor, so $100-$150. Keep an eye out for a coupon from your local dealer - sign up for their email lists. mine sends one out about every other month. Also, I believe this will qualify you for a year of MB Roadside Assist. Remember, they changed that program several years so the "lifetime" provision only applies to original purchasers and CPO cars; subsequent owners only get to use it if they have an annual visit to the dealer.

I recently got my transmission rebuilt 15,000km ago and a new radiator (Baer). Don't wanna trash it again -_- reason it got replaced because coolant went into the tranny. The culprit was the Valeo rad. I got 5000km ish on the warranty so if it does break b4 that, ill b ok lol.

Servicing with full fluid change [including torque converter] every 60,000kms or 3 years. No problemo!! they will take it:y

Rogue-CLK:
I would think that the issue would surface earlier than this, your car had the Valeo since day one. At what mileage did you transmission start to fail?

It shouldn't be any problem. I mean.. your tranny failed previously because of the coolant and radiator. Now that its fixed you should be good to go.

How much did the tranny rebuild cost you?

I am also surprised the transmission needed replacement because of coolant contamination. Usually, shifting is so bad that it gets fixed before any damage can be done.

Thanks Rudney & Glyn. I get all my services done at the dealer - I actually like my SA because he is a Benz Enthusiast (just got an CPO E63 wagon with p30 :) )

He gives me a good deal - i'll ask about the flash next time I'm in. That is exactly what it does, clunks when coming to a stop when shifting into first. I might have a memory lapse - but i don't recall it doing that before I did a 39k trans fluid flush....

Got the car at 187,000 KM it happened at 190,000 km

Got quoted at the dealer for $4500 but got it done at a local Indy for $3000 including new rad

How would I know if I have the latest TCU codes for my transmission?

You need to check software edition with a Star.

On a side note.. other things can also get damaged besides the transmission...

.... I beat on my last C Class (manual).. dropped the clutch one too many times and took a huge chunk out of the rear differential. I doubt this would ever happen with an automatic.