This is a DIY for the replacement of the guibo, centre support bearing and transmission mounts for a 330Ci convertible with the ZF auto transmission.
I know a lot of this information is already out there, but having searched extensively prior to the job to get as much info as possible, I found there were gaps in the information I needed. Hence this DIY.
This DIY is for the driveshaft that has the rear CV joint (that bolts to the diff), so it won’t apply to all cars.
The reason for the DIY was a small vibration that occurred when accelerating through about 50km/h. I actually did the job four times inside 2 weeks. The first was on a mates 330 coupe, and then I did my car. Unfortunately after I did my car, the vibration was a lot worse. I took everything apart again, and thought initially it was the support bearing not being secured correctly. This turned out to be wrong, and when I took everything apart again, it was actually a dud part. The rubber support to the bearing was already split (it was very thin and very different to the original part). I purchase a new bearing only from my local bearing dealer, and pressed it into the old bearing support, which was still in good condition. This finally fixed the problem, and the car now drives like new.
Whilst I was a little disappointed to have done it four times, in the end I had a pretty good idea of how to do it in the most effective manner.
Before I start the DIY, I’m someone who is a big fan of removing components to make other tasks easier. I’ve seen other DIY’s that leave stuff connected that I remove. Your choice.
Once the car is off the ground, remove the rear wheels. It’s going to make some tasks later easier.
First job is to remove the exhaust. If you have a convertible, you will first need to remove the tension strut at the rear underside of the car. The large bolts at the end have a lot of torque on them 59 Nm + 90deg, so you may need to use a breaker bar with an extension. You need to replace these bolts for installation.
There is no need to get original bolts from BMW. It is far cheaper to go to your local high tensile bolt dealer and get the equivalent and put a washer on it. I've got a bag of these ready to go for each time need to replace them. The bolt is the same as what goes on the front cruciform reinforcement place under the engine. The spec is M10 x 35 - 10.9 ZN.
Prior to exhaust removal, ensure you pull off the rubber hose connected to the bellows on the rear muffler.
Removal of the exhaust requires three sets of bolts/nuts to be removed. The most forward, that connect to the catalytic converters, can from what I understand from other posts be very difficult to remove. I’ve never had any problems. Each time I remove the exhaust I apply some copper anti seize paste to the bolt threads, and also to the gasket so it comes apart easily each time. I’ve removed the exhaust about 5 times and never had any problems. Also, a convertible is slightly different to others with respect to the center support point. It should be pretty obvious what you need to do.
Unless you are really organised with supports, etc, this is a two person job. The best way I’ve found to remove the exhaust is to remove all the bolts at the centre support bracket first. Then remove the 4 nuts at the front that connect to the catalytic converters. The exhaust will sit on the bolts that stick out. Now with someone supporting the muffler at the rear, remove the four nuts that hold the rubber mounts at the rear muffler. Now go to the front, and slide it rearwards to pull it off.
Once the exhaust is removed, now remove the heat shields. There are two that need to come off, the large one at the rear, as well as a small one forward of this on the right.
You will now see the driveshaft. Prior to anything else, put the gear lever in N. This will allow you to turn the wheels and driveshaft as required to have access to bolts. To lock the driveshaft so you don’t have to continually jump inside and put on the park brake, here is a simple solution. Get two good sized screwdrivers and put one in each rear brake calliper as shown in the photo. This will lock the rear wheels when you want to loosen/tighten stuff. When you want to turn the driveshaft, just remove one of the screwdrivers and turn the driveshaft. Put the screwdriver back in place to then work on the next bolt.
First job is to loosen the bolt that holds the two halves of the driveshaft together. You are just going to loosen it and nothing else. This is because it is difficult to hold the driveshaft and apply the required torque to loosen (or tighten on installation). You will separate it later once out of the car.
Next support the transmission. Do it solidly, as it will wobble about a bit as you remove the guibo bolts. When you support the transmission, do it by the edges of the pan. DO NOT support it under the center of the pan. Inside the transmission there is a gap of a few mm at most between the pan and where the filter draws in fluid. It would be very easy to bend the pan and create problems for fluid flow inside. I’ve seen pictures of people doing this floating around the web, and it makes me shiver. I would definitely suggest supporting it by the edges. You don’t have to support it on both sides like I’ve done here. I just did this to make absolutely sure it wasn’t going to fall. On my third and forth times doing the job I only used one support.
Once the transmission is supported, the transmission support bracket needs to come off. This has the transmission mounts attached to it. It needs to come off to you have access to the guibo bolts. Remove the bracket by loosening the top nuts on the mounts, removing the four bolts that hold on the bracket, and then slide it rearwards. Reverse for installation. You can see from the picture below that the old mounts are compressed significantly, and definitely required replacing. There are notches and knobs in the mounts that show how they are to go on.
Now remove the guibo bolts that attach to the transmission. Don’t remove the bolts that attach to the driveshaft. The guibo will come out with the driveshaft. Both ends of the bolts are 18mm. When installing, ensure you turn the nut end (closest to the transmission) and hold the bolt end steady.
When the bolts are out of the guibo, it won’t fall off. It has to move about 1 inch rearward to come off the transmission output shaft, so there is no problem with removing all the bolts now.
Now go to the other end of the driveshaft. To get the CV joint out, you first need to remove the bracket that is at the front end of the diff.
First remove the small heat shield.
Now remove the bracket. You don’t need to support the diff, as it will stay in place no problem. Once the bracket is off, put the two big nuts back on for the rear subframe and tighten to hold everything in place while you do everything else. You need to remove this bracket so you can remove the rear CV joint.
Now remove the 6 torx bolts that attach the rear CV joint. Once these are out, get a large flat head screwdriver and lever out the joint. When it comes free, due to its dimensions, it won’t fall down, and will sit there nicely. When installing, insert a bolt on each side, and gradually pull the joint in evenly until it is seated in place.
Now it’s time to remove the driveshaft. Both ends should be loose, so all you need to do is remove the two nuts that hold on the center support bearing, and pull down. When you pull down at the bearing, hold the CV joint at the rear, as it will come free first. When the CV joint has dropped free, and you have pulled the bearing bracket down (there will be lots of butyl tape trying to hold on and making a bit of a mess as you do this) you can slide the whole driveshaft about an inch rearward, and the guibo end will come off the transmission output shaft. It’s not heavy, and is easily a one person job.
When you have the driveshaft out, the first job is to separate the two halves. Ensure prior to separating you scribe marks on each side to show you where to align it later. The shaft is balanced as a single unit, and if you don’t put it back the way you found it, it will most likely vibrate.
Remove the bolt that you previously loosened.
To separate the two halves, with the bolt removed, it should just pull apart. It may be corroded, and you may need to give the transmission flange end a bit of a hit with a mallet to get it to move.
Once the two halves are separated, you now want to remove the bearing. I used a standard bearing puller as shown. I’m sure a 3 jaw puller or something like that would work fine.
Putting on the new bearing is simple. You can use a socket or pipe piece like I’ve shown in these photos, or you can tap it a little into place, and then join the two halves of the driveshaft, and install the bolt. Tightening the bolt pulls the bearing easily into the correct position. Ensure the bearing isn’t back to front.
I know a lot of this information is already out there, but having searched extensively prior to the job to get as much info as possible, I found there were gaps in the information I needed. Hence this DIY.
This DIY is for the driveshaft that has the rear CV joint (that bolts to the diff), so it won’t apply to all cars.
The reason for the DIY was a small vibration that occurred when accelerating through about 50km/h. I actually did the job four times inside 2 weeks. The first was on a mates 330 coupe, and then I did my car. Unfortunately after I did my car, the vibration was a lot worse. I took everything apart again, and thought initially it was the support bearing not being secured correctly. This turned out to be wrong, and when I took everything apart again, it was actually a dud part. The rubber support to the bearing was already split (it was very thin and very different to the original part). I purchase a new bearing only from my local bearing dealer, and pressed it into the old bearing support, which was still in good condition. This finally fixed the problem, and the car now drives like new.
Whilst I was a little disappointed to have done it four times, in the end I had a pretty good idea of how to do it in the most effective manner.
Before I start the DIY, I’m someone who is a big fan of removing components to make other tasks easier. I’ve seen other DIY’s that leave stuff connected that I remove. Your choice.
Once the car is off the ground, remove the rear wheels. It’s going to make some tasks later easier.
First job is to remove the exhaust. If you have a convertible, you will first need to remove the tension strut at the rear underside of the car. The large bolts at the end have a lot of torque on them 59 Nm + 90deg, so you may need to use a breaker bar with an extension. You need to replace these bolts for installation.
There is no need to get original bolts from BMW. It is far cheaper to go to your local high tensile bolt dealer and get the equivalent and put a washer on it. I've got a bag of these ready to go for each time need to replace them. The bolt is the same as what goes on the front cruciform reinforcement place under the engine. The spec is M10 x 35 - 10.9 ZN.
Prior to exhaust removal, ensure you pull off the rubber hose connected to the bellows on the rear muffler.
Removal of the exhaust requires three sets of bolts/nuts to be removed. The most forward, that connect to the catalytic converters, can from what I understand from other posts be very difficult to remove. I’ve never had any problems. Each time I remove the exhaust I apply some copper anti seize paste to the bolt threads, and also to the gasket so it comes apart easily each time. I’ve removed the exhaust about 5 times and never had any problems. Also, a convertible is slightly different to others with respect to the center support point. It should be pretty obvious what you need to do.
Unless you are really organised with supports, etc, this is a two person job. The best way I’ve found to remove the exhaust is to remove all the bolts at the centre support bracket first. Then remove the 4 nuts at the front that connect to the catalytic converters. The exhaust will sit on the bolts that stick out. Now with someone supporting the muffler at the rear, remove the four nuts that hold the rubber mounts at the rear muffler. Now go to the front, and slide it rearwards to pull it off.
Once the exhaust is removed, now remove the heat shields. There are two that need to come off, the large one at the rear, as well as a small one forward of this on the right.
You will now see the driveshaft. Prior to anything else, put the gear lever in N. This will allow you to turn the wheels and driveshaft as required to have access to bolts. To lock the driveshaft so you don’t have to continually jump inside and put on the park brake, here is a simple solution. Get two good sized screwdrivers and put one in each rear brake calliper as shown in the photo. This will lock the rear wheels when you want to loosen/tighten stuff. When you want to turn the driveshaft, just remove one of the screwdrivers and turn the driveshaft. Put the screwdriver back in place to then work on the next bolt.
First job is to loosen the bolt that holds the two halves of the driveshaft together. You are just going to loosen it and nothing else. This is because it is difficult to hold the driveshaft and apply the required torque to loosen (or tighten on installation). You will separate it later once out of the car.
Next support the transmission. Do it solidly, as it will wobble about a bit as you remove the guibo bolts. When you support the transmission, do it by the edges of the pan. DO NOT support it under the center of the pan. Inside the transmission there is a gap of a few mm at most between the pan and where the filter draws in fluid. It would be very easy to bend the pan and create problems for fluid flow inside. I’ve seen pictures of people doing this floating around the web, and it makes me shiver. I would definitely suggest supporting it by the edges. You don’t have to support it on both sides like I’ve done here. I just did this to make absolutely sure it wasn’t going to fall. On my third and forth times doing the job I only used one support.
Once the transmission is supported, the transmission support bracket needs to come off. This has the transmission mounts attached to it. It needs to come off to you have access to the guibo bolts. Remove the bracket by loosening the top nuts on the mounts, removing the four bolts that hold on the bracket, and then slide it rearwards. Reverse for installation. You can see from the picture below that the old mounts are compressed significantly, and definitely required replacing. There are notches and knobs in the mounts that show how they are to go on.
Now remove the guibo bolts that attach to the transmission. Don’t remove the bolts that attach to the driveshaft. The guibo will come out with the driveshaft. Both ends of the bolts are 18mm. When installing, ensure you turn the nut end (closest to the transmission) and hold the bolt end steady.
When the bolts are out of the guibo, it won’t fall off. It has to move about 1 inch rearward to come off the transmission output shaft, so there is no problem with removing all the bolts now.
Now go to the other end of the driveshaft. To get the CV joint out, you first need to remove the bracket that is at the front end of the diff.
First remove the small heat shield.
Now remove the bracket. You don’t need to support the diff, as it will stay in place no problem. Once the bracket is off, put the two big nuts back on for the rear subframe and tighten to hold everything in place while you do everything else. You need to remove this bracket so you can remove the rear CV joint.
Now remove the 6 torx bolts that attach the rear CV joint. Once these are out, get a large flat head screwdriver and lever out the joint. When it comes free, due to its dimensions, it won’t fall down, and will sit there nicely. When installing, insert a bolt on each side, and gradually pull the joint in evenly until it is seated in place.
Now it’s time to remove the driveshaft. Both ends should be loose, so all you need to do is remove the two nuts that hold on the center support bearing, and pull down. When you pull down at the bearing, hold the CV joint at the rear, as it will come free first. When the CV joint has dropped free, and you have pulled the bearing bracket down (there will be lots of butyl tape trying to hold on and making a bit of a mess as you do this) you can slide the whole driveshaft about an inch rearward, and the guibo end will come off the transmission output shaft. It’s not heavy, and is easily a one person job.
When you have the driveshaft out, the first job is to separate the two halves. Ensure prior to separating you scribe marks on each side to show you where to align it later. The shaft is balanced as a single unit, and if you don’t put it back the way you found it, it will most likely vibrate.
Remove the bolt that you previously loosened.
To separate the two halves, with the bolt removed, it should just pull apart. It may be corroded, and you may need to give the transmission flange end a bit of a hit with a mallet to get it to move.
Once the two halves are separated, you now want to remove the bearing. I used a standard bearing puller as shown. I’m sure a 3 jaw puller or something like that would work fine.
Putting on the new bearing is simple. You can use a socket or pipe piece like I’ve shown in these photos, or you can tap it a little into place, and then join the two halves of the driveshaft, and install the bolt. Tightening the bolt pulls the bearing easily into the correct position. Ensure the bearing isn’t back to front.