How to Remove the Propeller Drive shaft + Changing center Bearing

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Propeller drive shaft CPR

Removing the propeller drive shaft (also called the center drive shaft) is necessary when you are removing the engine/transmission, changing the flex disks or removing the differential/ rear subframe.

The procedure is similar to most cars and it is exactly the same for W126 and many Mercedes models. So guide this will work for both. Expect some wrestling and sweat underneath the car since the bolts can be very tightly on.

Theory

I highly recommend to change the center bearing, the center bearing carrier and front and rear flex disks when you remove the drive shaft for whatever reason, simply due to the long time of the job it would be a waste unless you also change these wearing parts with limited life span.

Practice
Removal

Step 1:
Remove the exhaust, check out How to Remove the Exhaust system
Step 2:
Remove the parking brake adjuster cables and springs. You will have to unhook the spring from the adjuster in order to get the cables off. The system is basically an adjusting rod with three cables attached to it and a spring to keep tension on the cable whem the parking brake is released.

Parking brake cable tightener
Remove this assembly to get more access to the drive shaft.

Step 3:
Now on to removing the drive shaft!

Loosen the sleeve nut in the middle of the drive shaft, this is to be able to collapse the drive shaft so it becomes shorter when removing it. Have a helper to apply the brakes so the shaft wont rotate when you try to loosen the sleeve nut. I do not like to apply pressure to the Transmission with the gear in Park due to the possible damage this may cause. Have the car in neutral instead.

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The Sleeve nut, needs a very large spanner”

Next step is to remove the flex disks, there are one at each side of the drive shaft. The bolts are of a self locking type (the nuts are not completely circular) and they are hard to remove since they are not meant to get loose when you drive. I actually broke my spanner trying to get one stuck bolt off, so here I recommend some long spanners or some form of extension on the spanners to get more torque. Remember simple physics where the torque = force x length, so the longer the better when loosening stuck bolts and nuts. To get the drive shaft off you only have to remove three nuts. The ones that are attached to the drive shaft spider. If you are planning on replacing the flex disk, then you have to remove all 6.

There might be tricky to access a spanner on the side facing the transmission, and you might end up supporting the transmission with a jack and removing the rear transmission mount.

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Front flex disk

Unfortunately you have to remove the three nuts at the differential end as well,  the access here is easier though.

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Rear flex disk

Now the drive shaft is hold in place by the center bearing carrier. The center carrier is just hold there by two bolts in the chassis.

drive shaft center bearing carrier
Center bearing carrier

Now you have to collapse the driveshaft by pushing the front side of the shaft in towards the middle to get it loose from the transmission spindle.

The drive shaft can be so corroded onto the flex disk mouting plates that you will not be able to do this easy by hand. I used a long screwdriver to place it between the drive shaft spider and the flex disk and used massive force until it broke loose.

Warning: You might end up damaging the flex disk which i did. It was so corroded that one tab of the flex disk broke off wæstill attached to the spider.

Caution: Be careful when handling the drive shaft so it doesn’t come slamming into the ground or on youself for that matter. The drive shaft needs to be perfectly straight and it is also balanced by the factory to a, so be careful eh?

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Drive shaft separated
Bearing Replacement

The bearing is most likely stuck in the drive shaft center carrier, always replace this cheap rubber part or your drive shaft will vibrate while driving. Just rip it off or use a knife to cut it so you can access the bearing.

The Bearing is pressed is pressed on the shaft and you need a puller tool like this. Note the placement of the dust caps around the bearing, so you place the the same direction when fitting the new bearing.

puller tool
Bearing puller tool

After pulling out the bearing, insert the new bearing into the new center carrier.

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Parts distributed, bearing dust caps, center sleeve, new center carrier and bearing, old one to the right.

Remember to insert the inner dust cap before tapping on the  new bearing.

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Inner beaing dust cap placement

Use a metal tube to tap on the inner part of the bearing, be careful with the hammering and do this slowly.

tapping on new center bearing driveshaft
Tapping on new center bearing on the drive shaft with a tube
Assembly

Assembly is pretty much the reverse as removal, however you need to spin the drive shaft around a few times after fitting, before tightening the sleeve nut, this is to remove stress on the drive shaft before tightening. The last thing you should do is tightening the sleeve nut!

Always follow the torque specifications on the flex disk bolts!

Cheers, Robs out

Author: robs

Passionate about older Mercedes Benz where driving, maintaining and learning new things is what keeps me doing this. Enjoying writing about cars and teaching others on the black arts of car maintenance. Have a major in space technology engineering and currently doing IT consulting for a living.

4 thoughts on “How to Remove the Propeller Drive shaft + Changing center Bearing”

  1. Dear Rob,

    Thanks a million for that well written instructions. I had tried to remove my drive shat but failed. Some how the clamps holding the flex discs would not let go. I tried to use a big screw driver but was not able to get it out because the drive shaft will not rotate. What can I do. Also you gave no instructions on how to remove the hand brakes. Thanks again. Have a great day.

    Onyeka.

    1. I updated the article to be a bit more descriptive, hope it helps!
      If your drive shaft will not rotate it means your parking brake is on or you have engaged Park on your automatic or have it in gear (manual). Remember the back wheels cannot touch the ground while you try to rotate the drive shaft. You need to be able to rotate your driveshaft in order to access the flex disk bolts and nuts.

    1. Dear Rob,
      I have completed the job. I am grateful. Thanks for your patience. People who understand cars get impatient when others ask questions with obvious answers, or over look some inconsequential instruction or explanation, which they assume is obvious to all. For people like me who never knew anything about cars until I came to US, every little explanation is very important. We are usually afraid to try and work on our cars because we might break it or do so much damage that it would cost much more to fix. Well I just want to say how much I appreciate not only your free DIY instructions, but also you patient effort to make sure we understand. Thanks a million!

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