Well here we are five years after I myself first read the line in the service manual and that
question is still popping up because of what was printed sixty years ago.
I believe the reasoning behind the spec was that the many of the greases back them were
soap based grease and would wash out from repeated exposure to the water splashed up
onto the open joint.
The other possibility is that the manuals were written by "Technical writers" who were
not engineers nor mechanics and they composed the text from what was explained to
them about the repair or maintenance process or what they observed the people doing on
the assembly line.
Back in the early sixties after high school one of my friends got a job as a technical writer
for a large corp. Tom had absolutely no mechanical ability whatsoever, he didn’t know
which end of the screw driver to hold but he did have a way with words. Having been
raised in a family of mechanics I had a pretty good eye for mechanical things by the time I
was in high school. I’d read some of the stuff that Tom had written for the companies
repair manuals and saw many discrepancies in his descriptions of procedures. One would
expect that an engineer would have reviewed the manual before it went to print but often
this didn’t/doesn’t happen. So today when ever I read a repair or assembly manual, I read
it with an air of skepticism, sometimes just plain common sense and years of personal
experience has to prevail.
I have, since the original thread was posted, been in contact with a few of the major
u-joint manufactures thru email messages and have been assured that NLGI #2 grade
chassis grease is an approved lubrication for modern day open universal joints.
Denny Graham
Sandwich, IL
