What Causes BMW Transmission Jerking?
2 Answers
Common causes of BMW transmission jerking: 1. Insufficient transmission response speed: Mostly due to the transmission's response speed being too slow, where upshifting cannot keep up with the throttle input, resulting in a jerking sensation during gear shifts. 2. Intervention of the energy recovery system: Often caused by the energy recovery system engaging. When the driver releases the throttle pedal or presses the brake pedal, the generator immediately starts working, placing additional load on the engine and affecting its speed, causing desynchronization between engine speed and clutch plate speed. 3. Turbocharger engagement at low RPM: Many BMW owners experience jerking during startup or at low speeds, typically due to turbocharger engagement at low RPM, which affects engine speed. Abnormal causes of BMW transmission jerking: 1. Gear programming issues: Problems with the transmission gear programming. 2. Internal contamination and debris (can be ignored for new cars): Dirt or debris inside the transmission prevents effective regulation of transmission oil pressure, leading to jerking. 3. Transmission cooling issues: Poor transmission cooling can cause abnormally high temperatures, affecting transmission oil performance. If temperatures exceed 120°C, the rubber sealing materials in the transmission can harden, leading to leaks and subsequent oil pressure issues, resulting in jerking.
I just started driving my BMW not long ago and noticed some transmission jerking. After searching online, I found many owners complaining about similar issues. The main reasons could be dirty transmission fluid from prolonged use or problems with the control module, affecting shift smoothness. My friend's car often behaves this way, especially during acceleration and deceleration, feeling jerky and uncomfortable. BMW's electronic systems are too complex—clogged oil passages or faulty sensors can also cause this. It's recommended to change the fluid regularly and inspect every 5,000 km. If you know a bit about DIY, first check the fluid level and top it up if low. Don’t overlook driving habits—sudden acceleration can cause jerking, while smooth starts are gentler on the transmission. In short, address small issues early to avoid major repairs later.
