A slight jerking when she's at 20-40 km/h. What is the cause?

[badass_ck]

Hi sifus,May i know if you have experienced this before.When the car starts running from 0 to 40 km/h or at around 20-40km/h, i find that thr car jerks a little (subtle but obvious as i can actually feel it). But, there are times which i don't feel it. This happens very seldom though.May i know:1) the cause of the problem?2) what is the solution?3) the costs?4) any long term side effect if not resolved?I was told that it is a gear box issue? Can any sifu enlighten me on this? Appreciate it! Thanks!Kind regards,

 

[seewai]

Could the jerk be the result of gear upshifting when you accelerate from 0 - 40km/h?
You mentioned there are times you don't feel it, are these the times you step harder on the accelerator?
Do you also feel the jerk if you decelerate (let go of gas pedal) mostly while going uphill and sometimes on flat road, from 40km/h - 0km/h?

 

[crusher]

I think it is time to change gear box oil

 

[gendong]

Sounds like gearbox issue. as per bro crusher's feedback, when was the last time you changed the gearbox oil?

 

[badass_ck]

Bro See Wai: mmm.... I didn't feel the jerk while decelerating though. No, the jerks didn't come from stepping the accelerator harder because I'd maintained the stepping of the accelarator to just get the car moving in a slow speed I.e below 40 km/h. And no, it is not due to the car climbing uphill too. Having said that, the did experience from a strong jerk after crossing a bumper.

Bro Crusher: noted! Hopefully, it will be ok after changing gb oil.

Bro Gendong: I'd just changed mine 2 weeks ago. This belongs to my bro's. Am actually asking on his behalf. So, I'm not sure when was the last time he did it but I shall advice him to do so to see any significance change to it.

 

[xcrave]

Did you check the Trailing Bush first? cause shifting will actually cause small Jerk if its too strong (close to earth shattering) then its Gearbox problem *Touch Wood

 

[ICEMAN 68]

maybe a weekening spark plug or ignition coil that's causing not enough current load to the engine ..try it out with and without aircond ..as running with the aircond ON, the load increases hence cause misfiring which may lead to this jerking ...

 

[badass_ck]

To all sifus,

I shall advice my bro to look into all this. Will keep all sifus updated accordingly. Thanks very much!

 

[santodiablo]

Hi, I have the same problem or may be more; mine does the same around 20km to 40km when the gears shift... It jerk/kicks forward, when decelerate also I have a pull/kick sometime. Please advice....thanking in advance

Note: I’ve change my ATF about 20000km ago (ravenol) not sure it’s the right choice , all rear axle bush, drive shaft Universal joint, engine mounting has been replaced.
E46 M43TU 1.9

 

[dvng]

I have the same problem on my E39. The problem is due to the Torque Convertor slipping. The only fix is to replaced it. Rm900 for recon unit and 7 litres of ATF oil.

 

[santodiablo]

Hi Guy’s, I’ve got mix answers from few BMW mechanic, one of the transmission specialist in Ara D’sara told me it’s the Transmission is starting to give way, use till it's con dam than do a complete overhaul, another told me it's the differential bearing which need to be changed (whole differential) as the no repair kit for it, and another told me, it's due to the ATF fluids I’m using (ravenol) should use the GM BMW ATF fluids...

guys, need your expert help, probably workshop who could give me a clear cut answer, so I don’t go chasing shadows...Bottom-line want to get this fix soon
Note: new spark plug (BMW ORI) plus Car Battery replaced

 

[santodiablo]

Hi guys, any advise on this matter? many thanks