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.

Attached Thumbnails

         

__________________
Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)

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.

Attached Thumbnails

         

__________________
Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)

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

Attached Thumbnails

       

__________________
Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)

You made it look easy!

__________________
'84 300SD sold
124.128

[QUOTE=Scott98;2176606]Step 10: Picture of rear driveshaft with old - if you were to pull the bracket off the driveshaft, it would take the carrier bearing with it.

The bearing rests on the mount shoulder when pressed in. The mount shoulder is adjacent to the shaft circlip when installed. If the mount were pulled off it may leave the bearing on the shaft. The mount deep V should be facing the differential.

I was under the impression that one would press the bearing into the rubber support mount prior to installing the bearing/mount onto the drive shaft. For the user(s) who mentioned placing the bearing in boiling water, did you install the rubber bearing mount after you installed the bearing on the shaft?

Or did you place the bearing/rubber mount assembly into a few layers of freezer zip lock bags, of which was placed into boiling water? If that is the case, would not the high temperature degrade the rubber components?

Analogous to your heating method, can the drive shaft centering sleeves at the front and rear of the drive line be frozen to ease with installation?

For those who did not use the hot water trick, how did you press the bearing onto the shaft if the soapy water was insufficiently slippery for the job?

On my 1979 240D, the rubber V-channel on the outer-most portion of the support has the narrower end of the V pointing towards the U-joint. Meaning that if the bearing-to-rubber support interface was all loose, the rubber support would pull off the spline-end and leave the bearing behind. There seems to be conflicting views on how this should be installed. I am not sure why.

Lastly, I was able to separate the splined intersection of my drive shaft without loosening the 46 mm nut. This seems to imply that I've been driving around with an untightened centre nut. What damage could this cause?

Is the reason for tightening the centre nut while the car is on all 4 wheels to set the proper drive line length for flat level operation? What about the cases when the car goes over bumps? On my Jeep, the drive line is meant to extend and contract with the terrain. Why is this not the case with these W123 vehicles?

Thanks a lot!

Nicely done.

__________________
DJ


84 300D Turbodiesel 190K with 4 speed manual sold in 03/2012

Good job. Great write up.

__________________
CJ

1983 300D 12X,XXX

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

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'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

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.

__________________
1985 Euro 300TD Turbo

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

__________________
Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)

Bookmarked! Thank you.

__________________
83 300TD, 260,000 miles, aka "Dusty"
6 vehicles, 2 cup holders (both in the dump truck)

This DIY is now in our DIY Wiki HERE.

Thanks Scott!

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Bill Wood - Retired Webmaster
My Personal Website
1998 Mercedes E430
2010 Toyota Sequoia
My Photo Albums

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

__________________
1981 240d aka "The rust bucket"

Is a w126 drive shaft bearing replacement the same?

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt