先前換了嘉實多與原廠建議同樣番號的油之後,結果聲音更大。
如圖:
之後剛好換了正確油的原廠油 (有寫著 +FM booster)後~ㄧ切安靜!
如圖:
這個問題在這邊已經有很多討論了。
總而言之,LSD會出現的主要狀況有三:
1.轉彎或是迴轉會嗡嗡叫,那就是你油該換了,或是油用錯了。
2.如果你是在直線換檔的時候會有控控的聲音,那是LSD齒輪之間的間隙變大了,那就是要維修或是整個換新,兩者選一。
3.如果你是開直線的時候,LSD後方傳來嗡嗡嗡嗡不間斷的聲音,而聲音隨著速度加快而便大聲,那就是軸承要換了。
如果您是情況1的話,您則只需要選用原廠正確的油~
如此而已。
最後: 嘉實多或是其他廠牌的SAF-XJ 與原廠 SAF-XJ + FM BOOSTER的差異在哪?
美國bmw很早就發佈公告,FM Booster 是一種添加的配方在SAF-XJ油裡面。 這種配方就是專門針對解決轉彎會嗡嗡翁問題的配方。
所以即使~今天你選了其他品牌~選了一樣是SAF-XJ,一樣都是75W-140或是更高等級的油,換來的都是潤滑保養的作用,但是SAF-XJ+FM Booster是特地用來針對BMW LSD的油。
因此,這就是為什麼很多人都會說: 呴~~M-power 的 LSD有夠挑的由來。
而如果您的症狀確定是因為油的問題,則在換上正確原廠LSD含FM Booster的油之後,需要在安全的空地上,方向盤打到底並且在原地左迴轉20圈後,接著在原地右迴轉二十圈,則可以讓FM Booster的配方完整個附著在LSD裡面。雜音則消除~^^
PS: 以上資訊接來自於美國BMW。
以下為原廠公告:
This Service Information bulletin supersedes SI B33 01 02 dated March 2008.
SUBJECT
Grinding Noise from the Differential during Slow Cornering
MODEL
E90, E92 and E93 M3 from start of production
SITUATION
A grinding noise may be heard coming from the differential during slow cornering. This noise is best heard during tight cornering situations; for example, while parallel parking, driving in a tight circle, etc.
CAUSE
When the rear wheel speed differential varies during tight cornering, a slip stick effect is created on the lining and steel discs incorporated in the differential locking clutch, causing the grinding noise. This noise typically goes away as the locking clutch discs in the differential are broken in.
The break-in time varies depending on driving habits; for example, tighter cornering (working the locking clutch) means that it takes less time to break in the locking clutch discs.
CORRECTION
If a customer complaint is verified as described above on the E46 M3; E60 M5; E63 and E64 M6; or on the E90, E92 and E93 M3 vehicles, the differential oil should be replaced with a specially formulated differential oil, BMW part number 83 22 2 282 583.
PROCEDURE
1. Drain the differential oil. Refer to the appropriate model repair instruction in TIS:
Main Group 33 / Subgroup 10 / RA 0011259.
2. Refill the differential with special differential oil as shown in the illustration below.
Differential fill capacity = 1.2 liters (1.3 quarts).
3. Road test the vehicle.
With the vehicle at operating temperature, drive in tight circles (20 circles in each direction), allowing the special oil to coat the locking clutch discs.
The grinding noise will decrease when the locking clutch discs are sufficiently coated. Some slight noises may still be heard after driving in tight circles. Advise the customer that it will be necessary to drive the vehicle up to 600 miles before all noises are eliminated.
Note: Vehicles that have had the differential oil converted to this special oil should continue to use this oil whenever a service requiring the differential oil replacement is indicated.