BMW M4: expert advice on gearbox maintenance

EDEN BOITES explains the various transmission problems you may encounter when driving your sports car. Find out how to repair your M4's gearbox. 

BMW M4 gearbox: what makes it special? 

The BMW M4 offers the option of a manual or automatic gearbox. 

The first generation M4 (F82 & F83) features a twin-turbocharged in-line 6-cylinder engine and a 6-speed manual gearbox. The M4 Coupé 3.0i 431 hp and the M4 Cabriolet Pack Compétition 450 hp are equipped with these. The M4 Coupé CS 3.0i 460 hp and other versions are also available with a 7-speed dual-clutch robotized manual gearbox. 

The more powerful second generation (G82) impresses with its in-line 6-cylinder TwinPower Turbo engine, producing 510 hp in its Competition version. For the first time, BMW introduces M xDrive, a 4-wheel-drive version equipped with all-wheel drive, enabling the car to be switched to rear-wheel drive.

The 6-speed manual gearbox has been retained, but the second-generation M4 is popular for its 8-speed M automatic gearbox with Drivelogic for rapid gear changes. It can be found in the M4 Competition Coupé 3.0i 510 hp and in the new M4 CSL, a special edition with a maximum output of 550 hp, the most powerful ever built. 

When should a gearbox be repaired?

The sooner symptoms of gearbox problems are detected, the easier it will be to resolve them. It's important to act quickly, and not overlook any signs of malfunction , to avoid costly repairs. 

For a BMW M4 mechanical gearbox, you should be alerted by the following signals: 

• Dull whirring noise, often caused by worn bearings;
• Abnormal vibrations while driving ; 
• Difficulty shifting gears: incorrectly adjusted clutch guard or damaged oil; 
• Crackling noise during gear changes may be a sign of worn synchronizer rings;
• Uncontrolled shifting of gears, frequently caused by damaged synchronizer sleeves or incorrect adjustment of the gear selector rod; 
• Oil stains under the car.

If your M4 has an automatic gearbox, these clues should warn you: 

• Screeching noise from automatic transmission ;
• Shifting gears abruptly, more slowly or with difficulty , sometimes due to mechanical failures ;
• Burning smell may indicate overheating ;
• Shaking during gear changes ;
• Frequent slippage caused by low transmission fluid pressure, speed sensor problems or worn clutch plates;
• Oil stains under the vehicle. 

How do I repair the gearbox on my BMW M4? 

Repairing a gearbox is a complex task requiring the intervention of a mechanical specialist. He or she will remove the gearbox, diagnose the problem and suggest maintenance solutions.

Here are the most common repairs: 

• Replacement of defective components such as drive shafts or bearings in the event of abnormal noise or vibration;
• Change of seals due to oil leaks; 
• Repair of the clutch, which can include changing the clutch disc for manual gearboxes, and the torque converter for automatic gearboxes;
• Reconditioning or replacement of mechatronics in case of difficulty or refusal of automatic gear changes;
• Transmission fluid change for dirty oil, to be carried out between 30,000 km and 60,000 km on a BMW. 

Do I have to replace the entire gearbox?  

In some cases, repairs by a professional mechanic are enough to bring a gearbox back to life. In other cases, however, a complete transmission overhaul is necessary. 

Your mechanic tells you that the gearbox on your M4 is completely out of order? Don't panic! EDEN BOITES is here to help. Discover our selection of BMW gearboxes with a 12-month warranty and the possibility of subscribing to an extended warranty offering numerous advantages. Take a look at our customer reviews and request a free quote online.