The early M5 with the smg (sequential manual gearbox) 7 speed have numerous tsb's and warranty campaigns. The shifting of the gearbox is up executed by pressure from the hydrualic pump that stores aaprx 80psi in the accumulater. This accumulator or pump has a hi chance of failing and when it does the car shuts down without warning. My car shut down in the middle of the intersection just recently. And I have had this pump replace twice out of warranty and once within warranty. A major flaw of the getrag smg 7spd. BMW discontinued this transmission but continues to raise prices on the replacement pumps as they know there is a high turnover of repairs. Please visit the BMW M forums as this topic is heavily discussed

- San Jose, CA, USA

With an smg transmission, when accelerating from a complete stop, there is a loud thump in the rear of the car as if somebody hit you from behind. It is very startling and I am sure something is wrong with the car. This is a common complaint among all BMW M5 drivers. I am surprised nobody placed a complaint about this yet.

- Bridgeville, DE, USA

On June 24, 2006, A-united leased the M5 through BMW of monrovia, formerly assael BMW. During the duration of the lease, A-united incurred less than 1800 miles on the M5 primarily because the M5's safety and reliability had caused serious concerns. From as early as November 2006, A-united began experiencing problems with the M5 when the unusual noise from the engine became louder and louder. Shortly, the M5 began hesitating to accelerate. On October 22, 2007, the M5 was taken to BMW of monrovia for routine service as well as the cautioned service engine light soon alert on the M5. The technician explained that the M5 had a defective brake booster pressure sensor and he discovered a fault memory in the vacuum sensor. He assured that he would take care of the problem and the service light as well as the unusual noise from the engine would no longer occur. Contrary to the technician's assurance, the noise continued and did not go away. The M5 experienced acceleration problems on and off. By June 27, 2008, it was due for another routine service and again, A-united expressed concerns for the unusual noise and problems with acceleration. The technician continued to represent that the M5 was operable, safe and in working condition since his conclusion was based on the fact that none of the complaints or faults were stored. A-united trusted the technician along with BMW of North America's ("BMW") sound reputation and continued to rely on such that the M5 had no problems. But, shortly thereafter, the M5's noise grew even louder than it ever was. The service engine light soon alert came on again. In October 2008, the M5 was lightly rear-ended by another vehicle because of the acceleration problem. This time, the M5's performance issues had resulted in an accident. The M5 continues to have noises and acceleration problems. Now, the passenger airbag defect has occurred as well.

- Alhambra, CA, USA