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Getting Some Jerking/shuttering As I Tap On Brakes Above 100km/h

hicas_posse
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hicas_posse Community Regular

hicas_posse

Posted
Posted

hey guys

i need some help. Basically of the past week i noticed that when i drive above 100km/h,

and tap on the brakes to slow down a little,

i find that there is some jerking/shuttering.

This happened a long time ago but after my major service , it gone away.

What could it be???

Godzilla32 Veteran

Godzilla32

Posted
Posted

Probably a warper rotor. you can try getting them machined, but first i would get a trained mechanic to feel what you describe to make sure it actually is excessive disc runout..

hicas_posse Community Regular

hicas_posse

Posted
  • Author
Posted
Probably a warper rotor. you can try getting them machined, but first i would get a trained mechanic to feel what you describe to make sure it actually is excessive disc runout..

that sounds pretty like it cause i had never had the discs (on the brakes) machined...

but weird-how come it happens above 100km/h? So it's not a case of the wheel balancing gone ugly??

if it's the rotors that need machining, can anyone tell me if i need a balancing and alignment done again since the brake rotors are removed for machining (and then replaced in)?

thanks!

Godzilla32 Veteran

Godzilla32

Posted
Posted

If its a wheel balance issue it would do it all the time at speeds 80+km/h even without brake application. If it only does it when you brake then its most likely brake problem. Ive also heard of worn castor rod bushes causing this but im not sure if it applies to the skylines.

You dont need to balance the wheels unless:

You rotate them

Have new tyres fitted

Feel a vibration like i described

You only need a wheel allignment if:

You have uneven tyre wear.

Notice the car pulls to one way when your on a flat uncambered road with your hands off the wheel.

The steering wheel is not straight.

Good luck,

Deren

blind_elk Grand Master

blind_elk

Posted
Posted

What do you class as "tap" the brakes.

If it was a warped disk, it would probably happen all the time, at all speeds.

Why not just simply back right off the throttle; the car will simply slow under friction / rolling resistance / wind resistance. Then pick up the throttle when your speed is back to near 100. Or ar you talking ABOVE 100?

hicas_posse Community Regular

hicas_posse

Posted
  • Author
Posted
What do you class as "tap" the brakes.

If it was a warped disk, it would probably happen all the time, at all speeds.

Why not just simply back right off the throttle; the car will simply slow under friction / rolling resistance / wind resistance. Then pick up the throttle when your speed is back to near 100. Or ar you talking ABOVE 100?

helllo :mellow:

tap on brakes : meaning I just half step the brakes and not fully. Either way i still feel the shuttering.

The shuttering happens very obviously when the car is above 100km/h (sorta like 140km/h and i try to slow down to 110km/h).

what do you suspect?

hicas_posse Community Regular

hicas_posse

Posted
  • Author
Posted
If its a wheel balance issue it would do it all the time at speeds 80+km/h even without brake application. If it only does it when you brake then its most likely brake problem. Ive also heard of worn castor rod bushes causing this but im not sure if it applies to the skylines.

You dont need to balance the wheels unless:

You rotate them

Have new tyres fitted

Feel a vibration like i described

You only need a wheel allignment if:

You have uneven tyre wear.

Notice the car pulls to one way when your on a flat uncambered road with your hands off the wheel.

The steering wheel is not straight.

Good luck,

Deren

hello deren,

thank you:) I got the bushes replaced last year so i figure I will have to take the car in to a brake specialist.

guys, how much do you think it will cost for machining the brakes and how long would it take? thank you all!

Godzilla32 Veteran

Godzilla32

Posted
Posted (edited)

It doesnt take long to do only about 30-45 mins for a pair which includes r&r. Going on $80 /hour labour it shouldnt cost too much. Im not sure if they charge you for the serive too..Probably do. I only do the work i dont know what the boss charges unfortunately. You also have to make sure the dics are not undersize. If they are you will have to replace them. Fronts have 30mm min. from memory, rear 16mm min.

I just realised you probably dont kwn a 32GTR. The specs i stated regarding scrap thickness are for that car. Thought you were someone else.

Edited by Godzilla32

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