2024 GLC43 Jerky Transmission
Terribly disappointing
Last week I took my 2024 GLC 43 in for service as the 1-2 shifting got real bad both upshifting and downshifting. It always seemed to stumble thru the first gears when softly accelerating (light pedal) which is why I took it in originally but the transmission started hard shifting 1st to 2nd gear even without much acceleration and when stopping would harshly downshift. MB service informed me of a new SW update that addresses the jerky shifting when I dropped it off.
They found fault code LI27.60-P-079083 whereby they rinsed the valves to resolve.
They performed the SW update informing me that they applied SCN coding of N179/1 and software flash of N62/4. This made a significant difference eliminating the stumbling/jerky (that the vehicle always had since new) and the braking is much better addressing the over sensitivity/lack of modulation.
The vehicle now drives up to par with the badge it wears, it is a completely different vehicle now. I was on the verge of trading it in but given that this resolved all the concerns I am keeping it as it drives great and has the performance edge which is why I purchased it in the first place..
I never post anything, but am now so folks are aware of the update given the significant improvement it makes. Hopefully this is helpful.
Last edited by TonyTV; Jun 22, 2025 at 10:58 PM.
The Best of Mercedes & AMG
“Good morning. The vehicle is heading to wash and will be ready for pickup in about 20 minutes.For the drivability concern, we test drove the vehicle and confirmed the complaint. We connected diagnostics and a battery charger, then performed a short test and found fault code LI27.60-P-079083. We followed the work instructions, confirmed proper fluid level, performed valve rinsing procedures, and completed stationary adaptations.Regarding the error message on the cluster, we performed a short test and found fault U186B29 and LI46.10-P-078012. We completed the outlined work, including SCN coding of N179/1 and software flash of N62/4. All faults have been cleared from memory.”
The transmission is completely unpredictable. One day it's smooth as butter, the other day it kicks and lunges.
I feel like it would stall at times, even in Comfort. Especially going uphill and stopping uphill.
Today it jolted big time upshifting from 2 to 3, legit scared me a bit. Car has less than 500 miles on.
I'm giving it a few more weeks but will already reach out to the dealership giving them a heads-up.
I have a 53 and am not a stranger to weird MB shifts, but this is something else. Otherwise love the car.
Last edited by RedHotPepper; Jun 27, 2025 at 03:17 PM.


Update on my saga with this car. Rough transmission continues to act up. The car is completely unpredictable. It is currently at the dealership where they are performing another "software update" as well as another standing adaptation. The car was there on 7/15 where the same thing was done and the problem was not solved. This brings my total days out of this car to 26 and climbing.
At this point i had no choice but to open a lemon law case with Mercedes. I am hoping for a full buy back. Does any one have any tips on the process itself? Has anyone experienced a buy back from Mercedes?







