I almost didn't post this, for Scott's narrative on the psychology of racing
so moved me that I simply wanted to let it resonate through the hallowed SOL
halls. Scott, thank you; though I don't intend to ever get into racing,
yours was a vivid account of That Which Sustains Us - le joie de vivre, the
thrill of feeling your blood feed your body and quicken your heart every
single day of your life, and knowing that everything you are and everything
you do is devoted to a vision, a purpose, a grand quest: the act of _really
living_, using all of your senses, wit, intellect, and emotion to explore
the meanings and implications of being a living, breathing, human being.
But my steering wheel still shakes.
The history: When I got the car last summer, one of the glaring problem spots
was the steering rack. Specifically, the rubber boots had long since split,
which, of course, means loss of lubricant and gain of abrasives (dirt). After
driving the car a few thousand miles with the rack in this shape, I took on
the task - installed new boots & clips, as well as tie-rod-end boots. I
didn't feel like pulling the rack from the car, so I left it on, and simply
cleaned it as best I could. The right-hand inner ball joint had a significant
amount of play, so I cranked on the locknut 'til it was gone. I put in the
right amount of 85/90 Hypoid and buttoned it up.
The symptom: At and above ~50 mph, the steering wheel "shimmies" when the
front suspension encounters anything besides a perfectly smooth, flat road.
I have a pretty good grasp of both Newtonian physics and my front suspension
and steering geometry, so I know that this is caused by some transient lateral
load at the tires. The tires get knocked a little bit "sideways" by the
bump, which moves the rack a bit, which wiggles the steering wheel. I had
originally thought that this behavior was due to the play in the ball joint,
but it hasn't gone away. The car is decidedly non-fun to drive in this mode.
So the object of the game is to damp these movements. I suspect that the
90 wt hypoid oil is supposed to provide this damping as well as perform
lubrication chores. It's quite possible that some of the oil I put in
leaked out while I was putting everything back together.
The question: Is this an accurate and complete diagnosis? My suspension
is in good shape; I've got new GTV8 A-arm bushings, and my kingpins and
wheel bearings are snug. Anybody have any additional thoughts? Is the bit
about the oil damping wrong? Could my sagging rear springs have anything
to do with this?
Happy weekend, all.
-todd
todd@mudbug.nrlssc.navy.mil
'74 MGB 99K mi
'84 VW Rabbit Diesel 176K mi (broken timing belt; immobile)
'84 Volvo 245GL 172K mi
'85 Nishiki Prestige custom (not ridden these days; make an offer)
"People said it because other people said it. They did not know why it
was being said and heard everywhere. They did not give or ask for
reasons."
- Ayn Rand, from _Atlas Shrugged_
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