I've read where its reccomended to mark the 2 halfs of a drive shaft when removing from the vehicle so that they are reinstalled in the same relative position later. If I'm using the front half from one shaft and the rear half from another, is there any special directions on how the spline fits together?

__________________
You can't always get what you want, but if you try sometime you just might find you get what you need.

I think that's what you call being extra careful. I'm unaware of any good reason for it. But, I would like to hear one if there is.

__________________
Remember, Safety Third!
'99 E300 Turbodiesel, '82 300TD, 1996 12V Cummins Turbo, '94 Neoplan - Detroit 6V92TA

The drivesghaft is factory balanced. So it is very important to assemble them as they came apart. Mixing a non matched front and back portion of the shafts may or may not cause an issue.

The balance of the new to each other shafts should be balanced on a machine really for best results. Not too hard to pull them again if a vibration is present. Myself I might try balance the front shaft to match the one taken off if I knew the match marking of the original frontshaft. Just duplicate it on the second short shaft and balace it the same as the old one. It would be tricky to do at home though.

When I pulled the driveshaft halves apart on my 240 in 2006 I didn't mark the halves and put it back together without knowing the original orientation. That was 70k miles and 6 years ago, I've never noticed any vibrations. I wouldn't worry about it too much.

__________________

Something about that just doesn't sound right. If the shaft is balanced, then it shouldn't make any difference. If the shafts are not balanced, and somehow depend upon their orientation relative to each other to balance... I'm still scratching my head on this one.

__________________
Remember, Safety Third!
'99 E300 Turbodiesel, '82 300TD, 1996 12V Cummins Turbo, '94 Neoplan - Detroit 6V92TA

The FSM shows that in about 1982 MB got their act together and put alignment marks on the two D shafts - and also say that the alignment marks were not paid attention to in assembly - so please correctly align them in service.

The marks are a triangle on one shaft and a square on the other.

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

The shafts should be balanced as a pair - a special relationship between the front and the back if you like.

If you take then apart and then refit them incorrectly the special relationship is broken => you could experience prop shaft vibration problems.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Zulfiqar kindly posted the FSM notes which mention both the alignment marks, and the fact that the marks were ignored at assembly time.

In the name of expediency, I have no problem blindly following the FSM advice, that's what I'd do, and what I'd recommend to anyone. But, as a general principle, I try to undertake projects in a mindful and purposeful way. While I understand that it is possible under limited circumstances, to balance shafts in such way. I can't see why anyone would ever think it is a good idea. Most especially an MB engineer. Can you explain why? Are you aware of any consequences for not doing so?

In typing this, I've just realized that like Biodiesel300TD, I have also used mismatched shafts in my TD, and noticed no problem.

__________________
Remember, Safety Third!
'99 E300 Turbodiesel, '82 300TD, 1996 12V Cummins Turbo, '94 Neoplan - Detroit 6V92TA

After a certain year they are marked by bumps on the Casting.

In another thread I speculated that he Prongs on the Yoke had a specife oreintationto the prongs of the Yoke on the opposiet end of the Shaft.
I think that means if there is no marks on the 2 shaft sections there is 3 positions that would work.

I don't have a good pic if the end with the Single Mark on it.

Attached Thumbnails

   

__________________
84 300D, 82 Volvo 244Gl Diesel

On the W123 we've got those rubber couplings, but they suffer from pretty much the same issue. thanks for the photos.

__________________
Remember, Safety Third!
'99 E300 Turbodiesel, '82 300TD, 1996 12V Cummins Turbo, '94 Neoplan - Detroit 6V92TA

Well, yes I am a little more then 1/2 way through the job of changing my Flex Discs; will finish that tomarrow tomarrow.

__________________
84 300D, 82 Volvo 244Gl Diesel

Thanks smiffy, the Tom Sotomayor link cleared it all up for me.

It's not a shaft imbalance problem, it is a limitation of U joints. There's a hint in the name of the u-joint's cousin, the Constant Velocity Joint.

__________________
Remember, Safety Third!
'99 E300 Turbodiesel, '82 300TD, 1996 12V Cummins Turbo, '94 Neoplan - Detroit 6V92TA

I only know the term Neutral Balance from the replacing of the Flywheel.

I take the term to mean that a Neutral Balanced Flywheel was one balanced all by itself. Where as the Flywheel that was balanced a long with the Crankshaft attached may or may not be Neutral Balanced; as, they could have drilled out some metal on the Flywheel when the whole Crank and Flywheel assembly was balanced.

In the case of the Drive Shaft I believe it would mean that each separate section of the Drive Shaft was balanced individually.

This is what is in part of the manual:
"The components of the propeller shafts are individually pre-balanced at the factory. To eliminate any residual unbalance which might still remain, re-balance the complete propeller shaft including the companion plates. For this reason, when dissembling the complete propeller shaft (e.g. when changing propeller shaft intermediate bearing) mark individual components in relation to each other (if no marks are in place) reassemble to the original Shape."

"On vehicles up to Jul 1982, mark the individual propeller shaft components in relation to each other.

On vehicles starting August 1982 the front and the rear propeller shaft ar marked in relation to each other.

Note: The identification has been partially already in place on propeller shafts prior to August 1982, but has no been taken into consideration during assembly. For this reason, propeller shafts on which the marking is not in agreement, must be identified prior to removal and the 2 parts must be plugged together following this identification."

The companion Plates are the Flex Discs.

So on one hand the Factory has the parts are pre-balanced but at the same time it recommends balancing "To eliminate any residual unbalance which might still remain".

So you assemble your Drive Shaft and hope for the Best. If you experience vibration and it bothers you find some way to Balance the Driv Shaft.

__________________
84 300D, 82 Volvo 244Gl Diesel

I've seen directions in a truck FSM where recommended procedure is to clamp 2 worm gear hose clamps to the drive shaft. If it is out of balance, move the relative location of the clamps until the shaft is balanced. I think a Dodge Ram with its poor quality control uses that method. 01 FSM is at pdftown for reference.

OP stated that he was using 2 halves but didn't say why. Perhaps he wants to take his chances with the parts on hand. In which case, a method of at least checking balance would be useful.

__________________
85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.

Converting an '87 190DT from auto to manual using a donor '85 2.3. Transmissions are different lengths. My readings indicate the rear halfs are the same length with the difference in the front halfs. Trying to perform the swap over a weekend. Would be a bit quicker I think to swap on the front half of the shafts rather than to change out the entire drive shaft. All this assumes everything bolts together of course. If it has the potential to cause problems, then I'll swap the entire shaft. Will probably need to swap the differentials eventually (again from my readings) but I don't know if time will allow over the weekend.

Thanks you for the indepth discussion of drive shaft balancing. I'm still not clear if there is a consensus as to whether swapping the front halves would create a problem though?

__________________
You can't always get what you want, but if you try sometime you just might find you get what you need.