How to replace the driveshaft support (carrier) bearing - A step by step guide

[Scott98]

Step 1: Mark the relative positions of the front and rear driveshafts. Also mark the relative positions of the front and rear flex discs.

Step 2: Get a 46mm and 41mm wrench and loosen the sleeve nut located on the front section of the shaft.

Step 3: Remove the front flex disc and compress the driveshaft.

[Scott98]

Step 4: Remove the front portion of the drive shaft.

Step 5: Remove the two 13mm bolts on the carrier support bracket.

Step 6: Note the circlip. You will need to remove this later.

Step 7: Remove the rear flex disc and remove the rear portion of the drive shaft.

Step 8: Picture of front and rear driveshafts removed and associated parts. The broken portion of my carrier bearing and bracket are still attached to the rear driveshaft.

Step 9: Remove the circlip. Get a large three jaw puller and remove the carrier bearing.

[Scott98]

Step 10: Picture of rear driveshaft with old carrier bearing and bracket removed. Also pictured are the new carrier bearing and bracket.

Step 11: Press the new carrier bearing into the bracket. I lubed the bracket with dishwashing liquid and pressed the carrier bearing in with my hands.

Step 12: The new carrier bearing and bracket are installed on the driveshaft. Don't forget to reinstall the circlip! The bracket has a shoulder which must face the rear of the car upon installation. The bearing rests against the shoulder when you press it into the bracket. Picture it like this - if you were to pull the bracket off the driveshaft, it would take the carrier bearing with it.

The last picture is of the gigantic wrenches you will need. Many of your parts/bolts may be rusted in place so be patient. My rear flex disc was seized to the driveshaft so I had to remove the flex disc from the differential to get it out of the car. You may be luckier than I was. Make sure you realign everything to match the marks you made upon installation so nothing is out of balance.

Good luck!

Scott

[lietuviai]

Nicely done.

[ChicagoJones]

Good job. Great write up.

[dieseldan44]

Thank you for the write-up.

You can get a big adjustable wrench at a plumbing supply store. I got mine at lowes, it opens very wide and has about an 8" handle.

dd

[disqo]

I just did this job two weeks ago on my '85 300TD and I needed a few extra steps. The manual advises disconnecting the parking brake cable and supporting the transmission from below in order to remove the transmission support. I took both of these steps. The parking brake cable can probably be worked around, but I did find it necessary to remove the transmission support to get better access to the bolts on the front flex disc. Also on my '85 there is no snap ring on the drive shaft. On the later year models there is another ring in it's place that is held on by friction and it requires the use of the bearing puller to remove the carrier bearing and the ring at the same time. I also had the car in neutral most of the time so that I could rotate the driveshaft by hand from underneath in order to access all of the flex disc bolts. Just be sure to use sturdy jackstands under the car. Overall it was not a difficult job, but it did take me a while and I had to spend quite a bit of time rolling around on my back under the car.

[compress ignite]

You made it look easy!

[Scott98]

Originally Posted by disqo

I just did this job two weeks ago on my '85 300TD and I needed a few extra steps. The manual advises disconnecting the parking brake cable and supporting the transmission from below in order to remove the transmission support. I took both of these steps. The parking brake cable can probably be worked around, but I did find it necessary to remove the transmission support to get better access to the bolts on the front flex disc. Also on my '85 there is no snap ring on the drive shaft. On the later year models there is another ring in it's place that is held on by friction and it requires the use of the bearing puller to remove the carrier bearing and the ring at the same time. I also had the car in neutral most of the time so that I could rotate the driveshaft by hand from underneath in order to access all of the flex disc bolts. Just be sure to use sturdy jackstands under the car. Overall it was not a difficult job, but it did take me a while and I had to spend quite a bit of time rolling around on my back under the car.

My car is a 4-speed manual and that may make a difference. There certainly are different ways you can go about it. This just lays out the basics and most people should be able to figure it out from there.

Scott

[disqo]

I certainly did not mean to imply that you had done anything improperly. I just wanted to point out potential differences for other folks that might be thinking about doing the work. I actually wish I could have seen your write up and pictures before doing my own. It would have saved me some time under there figuring out what was what. Thanks for the write up and pictures.

[marfa300td]

Bookmarked! Thank you.

[Bill Wood]

This DIY is now in our DIY Wiki HERE.

Thanks Scott!

[jaschanks]

Nice job! I needed that. Mine needs done to.

[oldsinner111]

Is a w126 drive shaft bearing replacement the same?

[TC_300SD]

What are the symptons to make you replace this?
I have been experienceing some "clunking" that sounds like it is coming from the middle to the back of my car. Could this be a remedy?

1983 300SD

Thanks

Tim