Drive Shaft Out of Phase (2 Viewers)

[arizona78]

Just got my cruiser back from getting a 3" Black Diamond lift installed. Noticed a driveline vibration at ~30mph. Probably there the whole time, but didn't notice it until the old stock springs were dumped. Anyhow, I searched the posts here and checked the driveshaft. The PO had the yokes turned 90 degrees out of phase. My question is this: Does it matter which direction (clockwise vs. counter-clockwise) I move the yoke to get the driveshaft back into phase? Thanks...

 

[DenverCruiser]

Don't think it matters.

 

[woody]

doesn't matter, so long as it's IN phase....it may have been balanced one way or the other, if you notice a very minor vibration after rotating, re-turn 180.

 

[IDave]

[quote author=woody link=board=1;threadid=14093;start=msg131036#msg131036 date=1080852620]
doesn't matter, so long as it's IN phase....it may have been balanced one way or the other, if you notice a very minor vibration after rotating, re-turn 180.
[/quote]

So that's what that little metal plate welded to the side of my rear DS is!......huh!

 

[mabrodis]

[quote author=woody link=board=1;threadid=14093;start=msg131036#msg131036 date=1080852620]
it may have been balanced one way or the other, if you notice a very minor vibration after rotating, re-turn 180.
[/quote]
Or you may always have a minor vibration no matter which way you turn it.

Only way to be sure is to have a driveshaft shop balance it. If you tell them that you think it's ok, just might need to be flipped 180 degrees, they may just put it on the machine and test it, then flip it and test it. Then realize it's not really 'balanced' either way. The shop I've been to charges $35 to fully balance it, so to just check it would be alot less I'd assume, maybe free if they are nice.

Good Luck...
Mark Brodis

 

[cavsfj40]

um, when you say it is 90 degrees out of phase, what exactly do you mean. I do believe, correct me if i am wrong, that the ujoints should be sort of , well, staggerd. i mean that when one, lets say the driveshaft yoke at the diff is vertical, the driveshaft yoke at the case should be horizontal. I THINK. it is raining here so i am not going out to get under mine. When my lift was new i got some vibes but it went away as it settled a bit.

 

[arizona78]

Thanks everyone for your responses. I just took a guess and rotated driveshaft 90 degrees clockwise at the diff end. The driveshaft yokes are now aligned to each other. Vibrations have decreased by maybe 80% or so. I may try rotating 180 degrees to see if that will decrease vibrations even more. Thanks again...

 

[Poser]

[quote author=cavsfj40 link=board=1;threadid=14093;start=msg131136#msg131136 date=1080864844]
um, when you say it is 90 degrees out of phase, what exactly do you mean. [/quote]

The tube end of the drive shaft has an end yoke welded to it, that holds two of the four bearing caps in the joint assembly. The female part of the slip and stub assembly also has two ears that hold two caps of the joint assembly. These ears, the front and the rear, MUST be parallel, or in phase, otherwise, the joints will not be working together, but rather, against each other, and vibrations, along with damage to the joint, shaft, the differential or transfer case can result.

The factory chassis and body manual covers this, and shows a picture of what I have described. If I were able, I would post up a picture.

Klear as mud?

-Steve

 

[IDave]

Here is the picture from the C&B Manual Steve refers to:

 

[Poser]

Thank you Dave.

 

[IDave]

Hey, I may not know what I'm talking about, but I know what YOU'RE talking about.....

 

[nocents]

Thanks for the picture....It IS worth a thousand words!

 

[woody]

http://www.4xshaft.com has a good tech corner too for d-shaft stuff....worthwhile read.

 

[Landpimp]

FYI, 80 series front driveshafts are OUT of phase and thats the way they are suppose to be.