[FWDLK] Vibrations, U-joints, and grease

["Tom Wright" <TWright669@xxxxxxx>]

Hi,
I've been having some strange experiences with my 57 Dodge.  Let me try and
give you the "short" story:
I had some rather annoying vibrations coming from my drivetrain between 65
and 75 MPH, which, of course, is the prime cruising speed.
In order to eliminate some of the variables, I replaced my U-joints.  I made
sure to pack as much grease as possible in the front "ball and trunion"
joint.  When I took my car on a road test, the vibration had become much
worse and steadily increased in amplitude from 55 untiul 75mph when something
went POP! and the vibration went away.
I checked under the car to see what had happened and noticed the rubber boot
had popped off and all the grease flew out.  However, my car ran smoother
than it ever had.
I went home, packed as much grease as I could from the back-side of the joint
(not much) and put the gaiter back on.  Now the vibration was back.  This
time there was another POP at 80mph everything smoothed out again.  I looked
under the car and this time the rubber boot had split open and thrown out all
the grease.  This is the way I have left it for the past few days and my car
is as smooth as ever.
What I don't understand is how 3 or 4 ounces of grease can cause my car to
shake so hard that my vision gets blurry.
Also, how much grease are you supposed to put in there, anyway?  Right now I
have only as much as wasn't thrown out by centrifical (centrifugal?) force.
(Until I put a new boot on, that is.)
Does anyone think something else is going on here that I just can't see?
Thanks for any insight,
Tom