Two-piece drive shaft phasing

[WorkinLonghorn]

I must have been asleep during this lesson.
I have a two-piece DS that vibrates and seems to go through middle u-joints too quickly.
Does anyone have a diagramn or description of how it is supposed to be phased? There is no special "alignment spline" like the haynes manual describes.
Thanks! WLH

[WorkinLonghorn]

OK I think I've got it; The transmission output flange is parallel to the one behind the center bearing and there's only the chance that one section is 180 degrees off, right?
Anyway while ;looking at it I noticed that the rubber thing aroung the center bearing alows the shaft to move at least 1/2 just with hand pressure and yet another u-joint is showing some play.

[gcburdic]

does this pic help any??...This is how the driveline shop set mine up...and I haven't had any issues...

[LONGHAIR]

Well, from the looks of it, gcburdic, yours is off (out of phase) but that appears to be in the welded section. I suppose that since it is the section that is held by the carrier bearing, it "theoretically" doesn't have an "opposing" joint on the other end. The important part of the phasing would be between the middle and rear joint. Those two would need to be aligned.

The joints are supposed to be "in-line". Say you lay your drive shaft on the garage floor, standing on the "flat" of the yoke. Then all of the joints should stand the same way. Now, I know that your carrier bearing is in the way of this, but you get the point? When they are aligned like this, each joint is doing the same thing, meaning compensating for the angle of the drive shaft, at the same time.

Many times there is a "dead" spline that will only let it slip together one-way...but not always. All of the others I have seen have had an odd number of splines. This makes it so that there is really no way for it to be assembled 180 degrees out of rotation. Even if this wouldn't effect the phasing, it could effect the balance of the shaft as a whole.

[tucnnuts]

i agree with longhair... the yoke are suppose to be inline , the two peice i used had two of the splines angled in a lil bit to index it...i have also had to put a slip yoke in the rear to help reduce the stress on the hanger bearing....mines not in the stock location but on a stock height truck , is it important to have the truck on the gound before you tighten the bolts in the hanger bearing or does it not matter?i have the wine glass style not the pillar block kind...

[gcburdic]

Originally Posted by LONGHAIR

Well, from the looks of it, gcburdic, yours is off (out of phase) but that appears to be in the welded section. I suppose that since it is the section that is held by the carrier bearing, it "theoretically" doesn't have an "opposing" joint on the other end. The important part of the phasing would be between the middle and rear joint. Those two would need to be aligned.

The joints are supposed to be "in-line". Say you lay your drive shaft on the garage floor, standing on the "flat" of the yoke. Then all of the joints should stand the same way. Now, I know that your carrier bearing is in the way of this, but you get the point? When they are aligned like this, each joint is doing the same thing, meaning compensating for the angle of the drive shaft, at the same time.

Many times there is a "dead" spline that will only let it slip together one-way...but not always. All of the others I have seen have had an odd number of splines. This makes it so that there is really no way for it to be assembled 180 degrees out of rotation. Even if this wouldn't effect the phasing, it could effect the balance of the shaft as a whole.

Well crap....I guess I'll run it over to them and have them take another looky....I really appreciate you input Longhair....I'd hate to be rollin' and have it go ca-put!!!....Thanks again! Geoff

CoachMeason...PM sent

[Green Machine]

Should be like this - each "long" piece should have the ears lined up -



yoke hanger Rear


==[0==========0]============[0

[COACHMEASON]

Not to jack the post but....gcburdic...how do those flows sound dumped under the truck like that and can you carry on a conversation next to you in the cab? trying to get ideas on my exhaust...are those 2.5 or 3 in pipes? Thanks

[Bus Ted Knuckle]

have you checked your transmission mount(s)? if they go bad, and are not replaced, they will take the carrier bearings and ujoints with them.

[cdowns]

its not that expensive to take to a driveshaft shop to have new installed and shaft balanced

[WorkinLonghorn]

have you checked your transmission mount(s)? if they go bad, and are not replaced, they will take the carrier bearings and ujoints with them.

its not that expensive to take to a driveshaft shop to have new installed and shaft balanced

The cheapest of the two DS shops around here told me $160 to balance a two-piece, which I thought was excessive.I did get him to look under, and he said it was out of phase.

It seemed good with just my two hands acting on it, I'll maybe look at it while applying some power through the trans and see if it moves,but i think it's OK.