Are W123 driveshafts indexed/marked? - PeachParts Mercedes-Benz Forum

nickofoxford · #1 10-17-2009, 04:55 PM

-sigh- Here goes.. I think I really messed up this time.

I recently bought an '83 300CD with a dead transmission. And in the process of installing another transmission, the driveshaft was separated without being marked, and installed just as good. I think I really messed this one up.. I didn't find any marks on the splines but I didn't look really good, so I figured it was neutral balanced.

I don't think such is the case, because from 25-30mph it shakes like crazy under full load. But if I give it anything under half pedal it behaves with minimal vibrations.

Basically, Is this what the problem is? And if so, can I find markings on the front and rear driveshafts and put it back together correctly?

Am I stuck with a four wheeled vibrator?

cth350 · #2 10-17-2009, 05:43 PM

Nope, one the drive shaft halves are separated and put back together at random like that, it needs to be balanced. It's easy to fix, but time consuming.

Just pull the shaft, deliver it to a shop that knows how to balance it and then put it back in.

Now's a good time to replace the carrier bearing and all that.

-CTH

bmwpowere36m3 · #3 10-17-2009, 06:05 PM

The driveshaft halves are indexed and balanced to each other, but the driveshaft is NOT indexed to the transmission and/or differential. Supposedly later style driveshafts are indexed with two "nubs" on one half and a single "nub" on the other half. You align the single nub between the two nubs on the other half. It's hard to explain, I know there a picture somewhere of it.

Most likely you'll need to have it rebalanced... or if you patient enough, keep indexing one half of the driveshaft till you eliminate the vibrations.

nickofoxford · #4 10-17-2009, 06:21 PM

Quote:

Originally Posted by bmwpowere36m3

The driveshaft halves are indexed and balanced to each other, but the driveshaft is NOT indexed to the transmission and/or differential. Supposedly later style driveshafts are indexed with two "nubs" on one half and a single "nub" on the other half. You align the single nub between the two nubs on the other half. It's hard to explain, I know there a picture somewhere of it.

Most likely you'll need to have it rebalanced... or if you patient enough, keep indexing one half of the driveshaft till you eliminate the vibrations.

I've seen what you're talking about, I don't think my driveshaft has any of that on it.. I knew I should of marked it first...

I'll probably wind up taking it all apart, moving it over 1 spline, and reassembling it.

nickofoxford · #5 10-17-2009, 06:24 PM

Quote:

Originally Posted by cth350

Nope, one the drive shaft halves are separated and put back together at random like that, it needs to be balanced. It's easy to fix, but time consuming.

Just pull the shaft, deliver it to a shop that knows how to balance it and then put it back in.

Now's a good time to replace the carrier bearing and all that.

-CTH

It got a brand new carrier bearing and center support already, along with flex disks. I really didn't want to get back under it this soon

. What kind of shop balances driveshafts? That's a new one for me..

tangofox007 · #6 10-17-2009, 06:39 PM

Quote:

Originally Posted by nickofoxford

What kind of shop balances driveshafts? That's a new one for me..

Look in the Yellow Pages under "Drives Shafts."

nickofoxford · #7 10-17-2009, 06:51 PM

Quote:

Originally Posted by tangofox007

Look in the Yellow Pages under "Drives Shafts."

Just like that, "Drives Shafts"

Thanks man, I do so much on the computer I never thought to look there.

fruitcakesa · #8 10-17-2009, 07:19 PM

I have had this driveline whine/vibration since I pulled my DS and put a new ctr carrier and bearing on and then reinstalled it. I had marked the shaft at the ctr spline and at the input and output ends so they would go back together balanced. I can't remember if it vibrated before since I only drove it a little before garaging it for last winter. I suspect my diff.

280EZRider · #9 10-17-2009, 07:57 PM

Quote:

Originally Posted by bmwpowere36m3

The driveshaft halves are indexed and balanced to each other, but the driveshaft is NOT indexed to the transmission and/or differential. Supposedly later style driveshafts are indexed with two "nubs" on one half and a single "nub" on the other half. You align the single nub between the two nubs on the other half. It's hard to explain, I know there a picture somewhere of it.

Most likely you'll need to have it rebalanced... or if you patient enough, keep indexing one half of the driveshaft till you eliminate the vibrations.

Starting in August 1982, the driveshaft halves are nubbed for alignment.

nickofoxford · #10 10-17-2009, 08:18 PM

Quote:

Originally Posted by 280EZRider

Starting in August 1982, the driveshaft halves are nubbed for alignment.

:

Like what bmwpowere36m3 was saying?? Two nubs on one shaft half and one nub on the other?

nickofoxford · #11 10-17-2009, 08:22 PM

Quote:

Originally Posted by fruitcakesa

I have had this driveline whine/vibration since I pulled my DS and put a new ctr carrier and bearing on and then reinstalled it. I had marked the shaft at the ctr spline and at the input and output ends so they would go back together balanced. I can't remember if it vibrated before since I only drove it a little before garaging it for last winter. I suspect my diff.

I was reading on a Volvo forum about center carriers, they were saying that if it's whining/vibrating it may need to be shimmed with washers. (further or closer from the body of the car) I'll see if I can find that page..

compress ignite · #12 10-18-2009, 03:16 AM

Before you torque the center carrier bearing support...AND...the Large DS Nut
roll the chassis back and forth 15-20 feet a couple of times to Pre-set the length.

fruitcakesa · #13 10-18-2009, 07:58 AM

Quote:

Originally Posted by nickofoxford

I was reading on a Volvo forum about center carriers, they were saying that if it's whining/vibrating it may need to be shimmed with washers. (further or closer from the body of the car) I'll see if I can find that page..

I also read that thread and after consideration decided against it as it moves things out of factory alignment and might cause other problems.

fruitcakesa · #14 10-18-2009, 07:59 AM

Quote:

Originally Posted by compress ignite

Before you torque the center carrier bearing support...AND...the Large DS Nut
roll the chassis back and forth 15-20 feet a couple of times to Pre-set the length.

I also did this to no avail.

DANSMB · #15 10-18-2009, 11:22 AM

I did the same thing and just kept adjusting it until smooth, they ended up being 1/3 of a turn apart or 120 degrees different.

Dan