N'AWLINS

First off a big compliment to the forum and its particpants. I used the forum to research before I bought and now use it to stay up on current issues.
Have been driving M-B's for 30 years and my GL is the first with the electronic stalk and 7 speed, so I'm having a bit of trouble getting used to it.
My observations....
*I can't shift "quickly" from reverse to forward like you can do in any other
M-B with mechanical shift linkage on the console. When I back out, then shift to forward quickly, the transmission shudders a bit before engaging. If I take my time, its fine.
*There is a very abrupt downshift (from 2 to 1, I believe) when I'm slowing to a stop. It's so abrupt it feels like I pumped the brake. Very aggravating.
*When slowing down (but not stopping),then accelerating, like in a turn, there is a hesitation (not the diesel) in the tranny.

Anybody experinceing any of these? I'm heading in for my 1000-3000 mile check and plan to have them investigate, but wnated to get some ammo here to help.

Thanks to all for a great forum.

scottybdiving

I haven't experienced the drastic downshift personally, but it has been discussed and I believe there is a software update available for this at the dealer. Somebody here will probably confirm this since several people have had the update done.

oknish

scotty is right, N'AWLINS. Take it to the dealer and tell them you have harsh 3 - 2, 2-1 downshifts. They will update tranny software. If you don't get far with them, let us know and I will find the TSB numbers that will help.

N'AWLINS

Thanks for the quick responses. Taking it to the dealer next week and will ask for the software upgrade.

Is the electronic shift stalk "delay" normal?

stlduckhunter

N'awlins, I got my GL about two weeks ago and am having exactly the same problems on the downshift. There are several threads about the problem here and I am just waiting to accumulate some issues and then take it to a dealer. Everyone says that the software upgrade will smooth it out.

Nevada Jack

You may need a software update but the problem should disappear with more driving as the transmission adapts to the style of driving. I had that in my S and the GL but the GL now is smoother than smooth (have a little of 7000 miles now.)

LEOSOPHIE

In my 550 I have only felt rough shifting when I don't make a complete stop and the transmission is in the process of making a 3-2 downshift. The 550 starts normally in 2nd, I don't know what gear the 320 starts in.

atwal

Things may go either way after you get the software update. I would be interested to see the results. During the break in period the tranny is learning the drivers behavior and adapts accordingly. Personally, I have felt that harsh down shift couple times but not that often. I don't have much of issue with it. But, in case the software update completely illiminates that harsh down shift I may get that done on ours as well. Please keep us posted with outcome.

Cheers!!

oknish

As NJ correctly points out, and you affirm, transmission learning does happen during break-in period. However, frequent rough/jerky downshifts are an anomaly and are not related to learning.

N'AWLINS

Duckhunter...sounds like we both have the same generation/run of transmission. I took delivery about 6 weeks ago.
After my dealer visit next week and hopeful software upgrade, I'll report back the results.
What a great forum!

N'AWLINS

Nevada Jack....reassuring to hear that the tranny will smooth out over time. I drove very cautiously with no downshifts or speed control for the first 1000 miles as recommended by many on this forum. I hope that cautious driving didn't "teach" the tranny some bad habits!!

Nevada Jack

That could well contribute to the downshift situation. I drive my new cars (which is pretty often lately) from the get-go like I normally drive. The S430 had a major problem but was fixed and I only had some minor tweaks with the S550. The GL so far has not presented any problems so far at least with the 550 engine.

N'AWLINS

Thanks Jack....I started driving my normal aggressive way today....we'll see how it goes from here!

jongaines

I am not sure shifting "quickly" from reverse to forward is recommended in any vehicle. Inasmuch as you are changing direction of the vehicle, I would think that waiting for the car to completely stop in one direction before changing to reverse or drive (as the case may be) would be appropriate. I am not trying to be judgmental, it just seems logical for the long term health of the tranny.

infamily

+1 agree 100%

N'AWLINS

Just picked up my car from the first complimentary service....which was nothing more than checking fluids and verifying if factory updates were needed.
I had them check the transmission....said there was an engine management software upgrade which among other things, effectively wipes out any "memory" that the tranny had learned. Effectively, it allows me to start over. Big difference noticed as soon as I drove out the dealer's driveway. So, don't dispair if you drove your truck gingerly over the first 1000 miles (like I did!!).

Also verified that there is no way to add the passenger mirror dip in reverse.

stlduckhunter

Got mine back last week after the first service. My only complaint was the transmission. The said there was a "recall" on it and reprogrammed the software. Well, I am a very aggressive driver, and the transmission shifting is worse that it was before. They are going to see it come back again.

N'AWLINS

Its been 300 miles since my transmission reprogramming at the dealer. Still have a hard downshift from 3 to 2 and now a smaller, but noticeable bump from 2 to 1.
So far, I'm really not impressed with this 7 speed electronic transmission

Nevada Jack

Give it another 500-1000 miles of good driving and it should smooth out for you. Don't baby it, drive your normal way. Also, drive in comfort and sport mode...it is my understanding the shift points are adjusted when you are in the different modes.

patsy1099

I only have 1000 miles so far on my GL. I do not baby it but rather get on it. It seems to shift pretty smoothly except when it's very cold and I punch it (I'm probably a moron for doing that anyway). One thing I've noticed is it really likes to wind out the gears. When I punch it, it almost always redlines the rpms before shifting. Normal?

N'AWLINS

How do you adjust for comfort and sport?

toothdr

most new cars will not let you shift from reverse to drive unless you are totally stopped if the engine shudders the computer is defueling the engine to save the rear end gears. if you come to a complete stop this will not happen

StevethePilot

You go buy a GL550. I don't think our CDIs have that option available.

I was not terribly happy with the whiplash deceleration in the 320, and I believe it is a diesel issue, but I can tell you that by 20,000+ miles I think it's smoothed out quite a bit. Then again, it's been a while since I've had a transmission reprogram, and every once in a while I get a lurch. Seriously, it's like it's programmed to engine brake, which is really not needed unless you're towing something.

Now there's a question; do you have the tow package on there? It might be over-programmed for downshifting when towing, and you might have a module that thinks it's towing all the time! Just a thought.

STP

blittle

Hmmmm......Interesting......I have the hitch on my 450 - did that option also involve a different program on the tranny? If so, I don't recall the literature saying anything about it.

N'AWLINS

STP....yes, I have the tow package. As you and Nevada Jack advise, I'll just keep driving normally and hope that it smooths out!!