I think I found the steering nibble cause
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Senior Member
Joined: Sep 2000
Posts: 568
Likes: 0
From: Tustin,Ca
I think I found the steering nibble cause
I think the steering nibble is caused by a combination of problems.
The root cause can be the A-arm pivot bushings. The more I look at the picture below the more it makes sense to me from an Engineering standpoint. Yes I are one, Engineer that is.
Let me try to explain my point. When you look at the rubber/polyurethane inside the bushing. The bolt goes thru the center of rubber. If the rigidity of rubber inside the bushing is too soft, then it would allow flexure of the A-arm under certain circumstances. That in turn would transmit motion back to rack and pinion. The rack and pinion being a precision type setup would respond to these slight motions and feed them back to the steering wheel.
Tire issues like vertical runout would cause minimal problems but on the other hand horizontal runout would be magnified by allowing resonance at certain speeds. So, with larger diameter tires the steering nibble would most likely occur at lower speeds.
Even a slight tire imbalance would also exagerate the problem.
This would explain a few things. It takes multiple tire balances to correct/minimize the problem. The problem may go away by a simple tire rotation. Installing the "green dot" rack and pinion assy. , that probably has been re-biased. Some may even require rotor and/or hub replacement, doubtful.
The bottom line is that the A-arm pivot bushing assemby needs to be redesigned along with rebiasing of the rack and pinion assy. That's my opinion and prediction of what will happen to cure this nagging problem.
The root cause can be the A-arm pivot bushings. The more I look at the picture below the more it makes sense to me from an Engineering standpoint. Yes I are one, Engineer that is.
Let me try to explain my point. When you look at the rubber/polyurethane inside the bushing. The bolt goes thru the center of rubber. If the rigidity of rubber inside the bushing is too soft, then it would allow flexure of the A-arm under certain circumstances. That in turn would transmit motion back to rack and pinion. The rack and pinion being a precision type setup would respond to these slight motions and feed them back to the steering wheel.
Tire issues like vertical runout would cause minimal problems but on the other hand horizontal runout would be magnified by allowing resonance at certain speeds. So, with larger diameter tires the steering nibble would most likely occur at lower speeds.
Even a slight tire imbalance would also exagerate the problem.
This would explain a few things. It takes multiple tire balances to correct/minimize the problem. The problem may go away by a simple tire rotation. Installing the "green dot" rack and pinion assy. , that probably has been re-biased. Some may even require rotor and/or hub replacement, doubtful.
The bottom line is that the A-arm pivot bushing assemby needs to be redesigned along with rebiasing of the rack and pinion assy. That's my opinion and prediction of what will happen to cure this nagging problem.
Senior Member
Joined: Apr 2004
Posts: 105
Likes: 0
From: above 7000 feet
just a simple question...
Do you have photo of the same joint with out the lift, cuase i do not seem to have any red under my truck. Black yes but red no. And if you do not have a lift did you paint something red?
If a lift is installed what is the chance that the installer did not install the list correctly or left a part out with the installed knowing about it.
Cause i do not seem to have any streening issues at all even on highway speeds.
Do you have photo of the same joint with out the lift, cuase i do not seem to have any red under my truck. Black yes but red no. And if you do not have a lift did you paint something red?
If a lift is installed what is the chance that the installer did not install the list correctly or left a part out with the installed knowing about it.
Cause i do not seem to have any streening issues at all even on highway speeds.
Senior Member
Joined: Apr 2004
Posts: 105
Likes: 0
From: above 7000 feet
cant wait to see what Rancho says....
I wonder if whne the added the lift if they should have replaced them. I guess you could have had a set of bad bushings or the bushings got damaged in the install...
Do you know how much new bushings cost?
I wonder if whne the added the lift if they should have replaced them. I guess you could have had a set of bad bushings or the bushings got damaged in the install...
Do you know how much new bushings cost?
