[Shotimes] Vibration or picky...again (update)

[cmichaelo@optonline.net]

And the saga continues...(update).

Tom, I checked for bearing grease on the inside of the knuckle (i.e., looking into the knuckle from the engine side.) No grease to be seen.  Totally dry in there.

Checked the seating of the rotor against the front right hub. The was a minor wobbling. Turned the rotor 72deg and it went away.

Checked the axle nuts all around.  All were at least 200 lbft.

Checked all other suspension bolts (strut pinch bolt, control arm bolts, tension strut nuts)...everything is fine.

I checked rotor lateral runout again with a dial indicator.  Rears are <0.001". So they are good.

CV joints:
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I did not check the CV joints yet.  They were checked 20k ago and were found in good condition by the mechanic. Bill, how do I check if CV joints are ok, or should I just replace them since they have 130k on them at this point?

Carrier bearing:
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Nor did I check the carrier bearing for the intermediate drive-shaft.

Dave, if this bearing is worn out, I should be able to measure that with a dial indicator, no?  Do you know what the spec is?  And I suppose it's a lot of work to replace that bearing, no?

Other clues:
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Here's two new clues to as what may be wrong. Hope you guys can help here:

1st clue - front right lateral rotor runout:

Let's say the dial indicator initially shows 50 (for 50/1000 of an inch). Then on the first single 360deg revolution the runout will typically stay within 49 and 51. But as I continue turning the rotor on the second 360deg revolution, it jumps to 52 or 53 and then stays between 51 and 52 (or 53) for the revolution. Then on the third revolution it returns to the 49 to 51 of the first revolution.

So this is so weird. You'd think that the fluctuation within a single 360deg revolution would be reapeted in the next revolution and in the next revolution etc. But it doesn't.

Whether I turn the rotor by hand or let the engine turn it in 1st gear makes no difference (though it is kind of hard to track the dial indicator at 800rpm in reverse.)

2nd clue - turning resistance.

When driving, and especially right after start-up, there is a resistance in the steering wheel when reaching a specific point when turning left.  You sort of have to turn harder to overcome the resistance.  Once it's overcome you can continue turning normal. 

It almost feels like the steering wheel is locked at this particular spot. And it's impossible to steer "finely" when at this particular spot.

This problem appeared suddenly about 4 years ago.  Could this be due to CV joints? Or is steering rack more likely culprit?


Michael
94MTX,green,BOS+,Koni/Intrax,Baer,Corbeau
SHO items for sale: http://hometown.aol.com/cmichaelo/for_sale.html