Dang! Knuckle replacement probs.

Thanks Bill,
But that doesn't help me understand/grasp the issue with loading the bearing(s). If this is true:

Then removal of ALL shims, which is what was done, should not have the same affect as with shims. That's counterintuitive. Can you explain?? I hope you guys don't grow angry with the hippster's perseverence in understanding the physics (or whatever) of "bearing load". Thanks!

 

unless the problem is on the other side
hence no change on the side you are working on
you have slightly upset the geometry of the front end
you may have been borderline before the problem happened
could a wheel weight have come off?
the kingpin bearings are for the knuckles to pivot on and allow the wheels to turn
the caster and camber (remember, have had 2 beers) are not adjustable, "built into" the knuckles and the axle housing
toe in is adjustable; did you have to loosen or adjust the tie rod end from the tube?
probably not
but something is off
the preload on the kingpin bearings is for "tension" while turning and driving; keeps the wheel from flopping around so to speak
a weak shock absorber, a glob of grease/mud inside the wheel, the wheel weights, lots of things can cause the wobble
Jim is the name

 

Jim, send a couple of those brauts over here....I've had nothing but cereal, mac & cheese, & ramen noodles the last few days. :evil:

That's what the FSM says to do, and yes that should be what this brother "should" do. My interest now is to not do that if I don't have to.
There has to be some wisdom to the addition & subtraction of shims, and I have yet to grasp what difference the tie-rod, backing plate, etc. have on that wisdom that would require me to go back to Pre-load rather than post-load. I know it's there somewhere. Can't the bearings be affected by changes in shims ex post facto? If so, how? If not, why?

Oh, I hadn't touched the other knuckle, so I doubt that'd be a variable. I guess anything's possible, though!

 

The shocks haven't been touched, and driving was fine b4. Wheel weights? Who knows, maybe something's up with that. I can certainly rotate tires and see if performance is enhanced, worsened, or no change. Good idea, and it's easy to do. Have another on me!

 

the adding/removing of shims controls the amount of load/tension you are putting on those bearings
you think removal of all should make the knuckle tight, not turn at all!
not true .... as the cap will only go down so far
try this: grab a hold of that knuckle and move it vetically up and down; you will probably have movement without the shims; this is not good, will hammer out the kp brgs and races
add the shims to eliminate the movement and bring preload to correct specs
just for fun, you sure neither one of the bearing races, especially the bottom, fell out when you took the knuckle off? you would have hade a lot of play

 

I know this is frustrating for you
but the answer is there
step back relax and think about it, and have a brew!!!!!

 

Alan (I hope)
do you have to hit a bump when this starts
or does it start say at 30 35 mph ?

 

Thanks for the help Jim. Yes I'm pretty sure that the races didn't fall out...aren't those sorta pressed in? I recall bending over to look up & seeing the race/seat. Bearings are good. In absence of a bearing packer, I hit each ball bearing with a grease needle. (new toy )

I doubt that the verticle up & down movement would do much because the tie-rod & seals & backing plate, etc. are all installed. At this point I'm just trying to comprehend the whole "bearing load" principle. It's a learning opportunity.

Back to your questions...the wander happens whether or not I drive 35MPh or 60. Even then, it's only randomly. I could be fine for a couple miles, then suddenly, I'm swaying to the right, then back to the left, then back to the right like I'm doing the tango. Then it stops for a while. No bump or anything seems to precipitate it. My thought is that it is the "shimmy" described in the FSM, especially because I hadn't had it prior to the knuckle swap.

 

Spring eye bushings? Even though I know you didn't mess with those, they might contribute, if they're on the edge.

 

the shims determine how much friction is there. spend the $$$ get a fish scale AND CHECK BOTH SIDES (should have 10-16 pounds of resistence). that is the only way you are going to know what is broke.

 

Between what and what? Bearing and seat prolly?

 

Bingo!!!

 

So Mike, can the bearing load be affected at all....by adding or subtracting shims....after everything else has been installed? Yes or no?

 

Yes, but you won't be able to measure it with the fish scale with the tie rod installed