95' 520i shfting clunk

[XDBoy]

Hello, new to here

as the title says, sometimes there's clunk when shifting, or espeacially when I release throttle and press clutch

I know it's 90% drivetrain related, drive shaft, diff joints, half shaft.. etc

last week I went to tire shop and had a change to look around:
https://www.youtube.com/watch?v=WzpmD6oOj8U


rear u-joint and diff /cv joint backlash seems fine, the problem might caused by the front u-joint

but it's hard to find the whole drive shaft in my counrty (Taiwan), we only have auto 520i everywhere (yes, a lot)

I know the 520i never been to US, but I think maybe someone has some experience here

I know there's option to replace the u-joint, but I can't find someone would like to do it (and do it well), too many bad cases

so I'm asking if I can only replace the rear section with auto drive shaft ? or I can just replace the whole shaft assy?



Thanks!

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[harambeto]

Where is the front U-joint? Behind the guibo? Or are you referring to the central support bearing? Are you able to shift smoothly or there is a wiggle every time and you simply cannot get a proper gear change especially in lower gears? If so, could this clunk be related to worn components like: gearbox mounts, differential mount, rear subframe mounts?

[XDBoy]

Where is the front U-joint? Behind the guibo? Or are you referring to the central support bearing? Are you able to shift smoothly or there is a wiggle every time and you simply cannot get a proper gear change especially in lower gears? If so, could this clunk be related to worn components like: gearbox mounts, differential mount, rear subframe mounts?

The front U-joint is behind the center support bearing, the 520i drive shaft is different to 525i which only has one U-joint and CV joint in the rear end.

as my understanding, the position of CSB and diff should be the same whatever auto or manual, include the diff mount shoud be the same either

so the difference between auto and manual drive shaft assy might be only the front section (my guess), to compensate the different gearbox length

as the U-joints are the only parts which to be worn out, I think it might be fixed by swap the rear section of auto one

but I just cannot find some more infomation

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