I drive an 87' 325is with ~198k on it:
Lately I have noticed a small amount of play in the drive train. I can never detect it when I am normally accelerating. But always when I go from accelerating the riding on engine compression there is a moment of 'freefall' and then the drive train suddenly engages, once it gets wound tight in the other direction.
From under my car it seems to be my differenial. There is no play in the u-joints, CSB, or guibo. But, I can turn the drive shaft a small amount (~5°) without turning the wheels and I can hear what seems to be the pinon and ring gear clack together as it reaches the end of the slop.
I know this isn't good, I am an M.E. student and at the least I know this means that the foot print on the pinon and ring is not right and that it is grinding way. I also worry that the high strain rates caused by the sudden engagment would be bad for the u-joints (although I am sure the guibo soaks up a fair amount of it).
In either case I should do something about it. I recently changed the diff fluid and it seemed to be very clean. If I can properly replace the pinion gear I would like to do that, however I have no experience in blueprinting.
Any suggestions on repair options or places to find a new diff would be appreciated, as well as learnings from anyone who has had this problem before.
I also checked the diff mount so I know it is not that.
I realize though that I didn't look to closely at the half shafts to see if a connection on them was the cause but I'll look soon and get back to you guys.
Thanks in advance, and sorry for the long post.
Lately I have noticed a small amount of play in the drive train. I can never detect it when I am normally accelerating. But always when I go from accelerating the riding on engine compression there is a moment of 'freefall' and then the drive train suddenly engages, once it gets wound tight in the other direction.
From under my car it seems to be my differenial. There is no play in the u-joints, CSB, or guibo. But, I can turn the drive shaft a small amount (~5°) without turning the wheels and I can hear what seems to be the pinon and ring gear clack together as it reaches the end of the slop.
I know this isn't good, I am an M.E. student and at the least I know this means that the foot print on the pinon and ring is not right and that it is grinding way. I also worry that the high strain rates caused by the sudden engagment would be bad for the u-joints (although I am sure the guibo soaks up a fair amount of it).
In either case I should do something about it. I recently changed the diff fluid and it seemed to be very clean. If I can properly replace the pinion gear I would like to do that, however I have no experience in blueprinting.
Any suggestions on repair options or places to find a new diff would be appreciated, as well as learnings from anyone who has had this problem before.
I also checked the diff mount so I know it is not that.
I realize though that I didn't look to closely at the half shafts to see if a connection on them was the cause but I'll look soon and get back to you guys.
Thanks in advance, and sorry for the long post.
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