Slipping Gears / No electronic fault detected on the diagnostics

[Lukasz2024]

Hi all I've been encountering what I think are transmission issues with my 2011 Mercedes C-Class Blue Efficiency Sport sedan lately. It feels like the gears are slipping, resulting in a less than smooth transition between shifts. When I accelerate, I notice a delay in speed increase despite the RPM rising. At times, the RPM spikes to 3-4k before stabilising around 2k. This happens each time I press gas. I haven't found any records of transmission or filter changes in the service book so hopefully that's that but it could be something more serious like the clutch on its way out.

There is also an oil leak from the cap, but my mechanic believes it's unrelated to the transmission problem.

has anyone experiences the same issues. I would appreciate any advice.

many thanks,

 

[Lukasz2024]

Hi all I've been encountering what I think are transmission issues with my 2011 Mercedes C-Class Blue Efficiency Sport sedan lately. It feels like the gears are slipping, resulting in a less than smooth transition between shifts. When I accelerate, I notice a delay in speed increase despite the RPM rising. At times, the RPM spikes to 3-4k before stabilising around 2k. This happens each time I press gas. I haven't found any records of transmission or filter changes in the service book so hopefully that's that but it could be something more serious like the clutch on its way out.

There is also an oil leak from the cap, but my mechanic believes it's unrelated to the transmission problem.

has anyone experiences the same issues. I would appreciate any advice.

many thanks,

Forgot to add that, the diagnostics didn't show any faults.

 

[Srdl]

Welcome - probably a full transmission service and fluid change would be a good starting point.

 

[malcolm E53 AMG]

If you have an oil leak the transmission may be low on fluid - as above get the transmission serviced low oil levels can lead to all sorts of problems

 

[Doug1234]

What are you reading the codes with ?, I would fully expect the ecu to pick up the high rpm surge ?

 

[rich.g.williams]

Which transmission please? What gear are you in when the flaring (unwanted increase in engine speed) occurs? Some amount of flaring is due to the way the torque converter works but should not be noticeable in higher gears.

ATF oil shortage a possibility, would expect some ETC (transmission computer) codes, after elimination of easier problems like ATF, speed sensors etc you are left with slipping clutch/brake rings inside the transmission. Normally slipping worn rings would affect only one or two gearshifts eg 3-4

How many km has this transmission done?