usinjin
06-28-2021, 09:27 PM
So a couple of months ago, I installed a replacement driveshaft in my sedan. The CSB and giubo both needed replacement, and my indy recommended I just buy a new driveshaft to avoid the hassle of replacing the CSB alone. I purchased a rebuilt one from driveshaftspecialist.
The install seemed to go okay. Driving the car, the clunking due to the dead CSB was finally gone. However, a new, much higher frequency vibration around 60mph+ has taken its place. It's a harsh buzz instead of a low speed clunk. At 80mph, especially on deceleration, the entire car buzzes like a swarm of giant bees.
I've ruled out everything else. Not tires, suspension, differential/engine/transmission mounts. The noise started immediately after installing the new driveshaft. My indy looked at my giubo for 0.5 seconds and said everything looked fine. I don't think the issue is with the giubo. Months later, it still looks perfect. OEM, with ALL new mounting hardware; yes, the arrows point to the flanges; yes, it's oriented properly for the load-bearing, aka post #9 from here: https://www.e46fanatics.com/threads/did-i-install-my-guibo-wrong.1127454/. Yes the torques are correct for it. The giubo is fine!
What I don't think is fine is the end that mounts to the differential:
38175
It appears the grease inside the part that mounts to the transmission has been spraying out. On the OEM driveshaft this part was sealed; the rebuilt one is not (the panel holding the grease inside falls off if the star bolts are removed). Also...is that gap okay? I had to pull it out (separate them) somewhat so that it would fit. (Is that the universal joint?) Is that crimped metal band supposed to be there? The whole thing just looks odd.
Any ideas would be appreciated.
EDIT: Here is the driveshaft I was sent (bottom one): http://www.driveshaftspecialist.com/Image/IMG%20import/BMW%20type%203.jpg
On the right side is the part that mounts to the differential. The bolts that came preinstalled in it (pictured) I had to hammer out and replace with the star-bolts that were previously installed in the car in the OEM driveshaft. The replacement ones were threaded, but the heads were flat--there was no way to install them into the differential holes! What the absolute...?
WHY is the whole process so convoluted??
The install seemed to go okay. Driving the car, the clunking due to the dead CSB was finally gone. However, a new, much higher frequency vibration around 60mph+ has taken its place. It's a harsh buzz instead of a low speed clunk. At 80mph, especially on deceleration, the entire car buzzes like a swarm of giant bees.
I've ruled out everything else. Not tires, suspension, differential/engine/transmission mounts. The noise started immediately after installing the new driveshaft. My indy looked at my giubo for 0.5 seconds and said everything looked fine. I don't think the issue is with the giubo. Months later, it still looks perfect. OEM, with ALL new mounting hardware; yes, the arrows point to the flanges; yes, it's oriented properly for the load-bearing, aka post #9 from here: https://www.e46fanatics.com/threads/did-i-install-my-guibo-wrong.1127454/. Yes the torques are correct for it. The giubo is fine!
What I don't think is fine is the end that mounts to the differential:
38175
It appears the grease inside the part that mounts to the transmission has been spraying out. On the OEM driveshaft this part was sealed; the rebuilt one is not (the panel holding the grease inside falls off if the star bolts are removed). Also...is that gap okay? I had to pull it out (separate them) somewhat so that it would fit. (Is that the universal joint?) Is that crimped metal band supposed to be there? The whole thing just looks odd.
Any ideas would be appreciated.
EDIT: Here is the driveshaft I was sent (bottom one): http://www.driveshaftspecialist.com/Image/IMG%20import/BMW%20type%203.jpg
On the right side is the part that mounts to the differential. The bolts that came preinstalled in it (pictured) I had to hammer out and replace with the star-bolts that were previously installed in the car in the OEM driveshaft. The replacement ones were threaded, but the heads were flat--there was no way to install them into the differential holes! What the absolute...?
WHY is the whole process so convoluted??