shaking when braking
shaking when braking
If i'm going fast like 60+ and i start to slow down for a light, or to get off the my car starts to shake like crazy especially the steering wheel, could a tire balance solve this? or perhaps new front rotors? How much does a tire balance cost?Thanks in advance
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Grant@tirerack
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Before you invest in a new set of rotors, try this easy procedure.You may want to try and re-bed the pads. Take a 'Scotch brite' pad and gently clean the rotor surfaces as best you can. Then take the car out and make 6-10 stops from aprox. 35 mph with moderate pressure. Make an additional 2-3 hard stops from aprox 40-45 mph. Do not drag the brakes. Then park the car and let it sit overnight. That will allow the brakes to cool off all the way and you should have a nice even transfer film on the surface of the rotor. When you bed in pads a thin layer of compound will stick to the rotor. If they are not broken in correctly that film will be uneven. When you apply the brakes the brakes will grab and slip, grab and slip as they hit the patches with the transfer film and then the bare rotor. That is what causes most vibration problems.
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
If you feel a fine quiver in the steering wheel at 60-70 mph and the tire are correctly balanced then lightly apply the brakes ----- keep foot on accelerator to maintain speed, the vibration intensifies and doesn't change frequency, then you know you have runout issues with the rotor.
On a well maintain car even a 0.002" runout is feelable using this method.
A single warp [high spot] will have a periodicity [frequency] of once per tire/rotor rotation [but a tire itself may also have 1-2 vibrations per revolution. These frequencies [peaks] can add or subtract and change with tire temperature [as the tire changes].
On a well maintain car even a 0.002" runout is feelable using this method.
A single warp [high spot] will have a periodicity [frequency] of once per tire/rotor rotation [but a tire itself may also have 1-2 vibrations per revolution. These frequencies [peaks] can add or subtract and change with tire temperature [as the tire changes].
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M3thod_Man
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You don't use your brakes when you accelerate, therefore it's most likely NOT a rotor problem.M3thod_Man wrote:When i'm in 5th gear and im accelerating my car makes a very low vibrating noise. Hard to explain, but its only when im accelerating and i only notice it in 5th gear. Is that most likely a rotor problem?
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offtheline
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M3thod_Man wrote:When i'm in 5th gear and im accelerating my car makes a very low vibrating noise. Hard to explain, but its only when im accelerating and i only notice it in 5th gear. Is that most likely a rotor problem?
Im guessing that this is not really a problem. There are such things as fundamental frequencies, and everything has one. A fundamental frequency is the lowest frequency at which something will vibrate. I believe that its possible that when you hit a certain rpm at a certain speed you can actually cause components of the car to vibrate. That might not be it, but Ive seen that happen.
