sonicboom188

Hi,
Wonder if anyone experienced the same issue where the vehicle (W166) failed to engage forward when the car was put into drive, and when stepping on the brakes to lower down the revs, a grinding sound could be heard?
Thanks

Hoplatani

Can you please give us more details on your car? YOB, BTC or Gas,... Etc

sonicboom188

It is 2014 ML550 gas engine with approximately 10000 miles on it mostly highway driven. Thanks

Hoplatani

Ho to the dealer an let them check the upper tranny, the y also have to drain the oil and see if there is metal in it! Then they should repar it and reinstall the software with the star system

Kenn1926

I have a 13' ML550. In the past on two occasions while driving at a steady speed the truck went into neutral. Gear selector said it was in drive. Had to pull over, turn off and restart the engine a few times to get it back to normal. This wasn't the tranny slipping, it was disengaged. Never had any grinding with it though. I do get a slamming into gear when coming to an abrupt stop while in sport mode. It feels as though I was rear ended. I'm used to it by now. When somebody new is in the car I just look at them, smile and proudly say "Mercedes, the best or nothing!" As an aside, you don't have an actual transfer case unless you have the on/off road package.

sonicboom188

Thanks for the input, I brought in the vehicle today to check on the problem. Hopefully, when I speak to the service advisor tomorrow, he might be able to explain exactly what might have caused the issues.

sonicboom188

I got back my vehicle. The dealer couldn't replicate the problem so all they did was update the software.... Very disappointed that they didn't try to find the cause, but at least it is documented. If I encounter the issue again, I will bring it back to the dealer.

Kenn1926

The cause is that the 7G transmission has problems. They need to start using the ZF 8 speed that is raved about in every Auto Union/BMW/Jag etc. My transmission has been "reflashed" and "updated" enough times that I don't bother mentioning anymore. Definitely the weak link in the 550's powertrain.