Vibrating Front End
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Joined: Jun 2005
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From: Sandy, UT/Fish Haven, ID
Vibrating Front End
I just put new tires all the way around and had an alignment but still getting a little front end vibration on my 95 C4. The vibration was there before the new tires and alignment.
It happens when slowing down.
Any insight what could be causing it?
It happens when slowing down.
Any insight what could be causing it?
Rennlist Member
Joined: May 2001
Posts: 16,140
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From: Eagle ID
If it is happening under braking, first clean out the holes in your rotors by pressure washing. If that does not work, I cured mine once by having the rotors lightly turned. If not that, you may need new rotors.
Nordschleife Master
Joined: Jun 2005
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From: Neither Here Nor There
You may have a bent wheel--which won't show up if you only had them spin balanced rather than Hunter Roadforce balanced. You could be feeling the vibration at only a range of speeds due to the harmonic associated with the bend.
Burning Brakes
Joined: Jun 2001
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From: A small horse farm in VA
Well
A bent wheel may be it....but in my experience it is always the rotors
Unlike Terry, I'd bite the bullet and put on new rotors on all wheels...also brake pads.......then you have a fresh start
Unlike Terry, I'd bite the bullet and put on new rotors on all wheels...also brake pads.......then you have a fresh start
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From: Herefordshire
Originally Posted by 95 C4 993
I just put new tires all the way around and had an alignment but still getting a little front end vibration on my 95 C4. The vibration was there before the new tires and alignment.
It happens when slowing down.
Any insight what could be causing it?
It happens when slowing down.
Any insight what could be causing it?
cheers, Maurice
Caliper Plate
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From: Eagle ID
Originally Posted by Berkley
Unlike Terry, I'd bite the bullet and put on new rotors on all wheels...also brake pads.......then you have a fresh start
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Instructor
Joined: May 2001
Posts: 165
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From: Altamonte Springs, FL
Do y'all follow the discussion on there is no such thing as rotor warp but rather brake pad particle transfer? I find I believe it when convenient 
and always go straight to it when rotors with minimum mileage on them start acting warped. That's about as scientific as I can get on it but it's worth considering. The "light turned" rotors is where I'd go first with nothing else being obvious (like a bent wheel.) The two bent wheels I've had on my 95 and an OTM could be felt accelerating as well as decelerating without any braking. Good luck!
and always go straight to it when rotors with minimum mileage on them start acting warped. That's about as scientific as I can get on it but it's worth considering. The "light turned" rotors is where I'd go first with nothing else being obvious (like a bent wheel.) The two bent wheels I've had on my 95 and an OTM could be felt accelerating as well as decelerating without any braking. Good luck!
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Thread Starter
Rennlist Member
Joined: Jun 2005
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From: Sandy, UT/Fish Haven, ID
This is ONLY when decelerating. Rotors and brake pads have 20k on them and I have never hit any to cause the wheel to bend. Most of my driving is in street so wear could be the factor. I have had the rotors turned once and my mechanic did mention that it could be time but would have to take a closer look.
Thanks for the insight.
Thanks for the insight.
Passed On
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From: Pittsburgh, PA
Is this decelerating with brakes on or off?
Brakes on? My experience has been rotors warped or have some material transfer. Have tried some rotor resurfacing if it's mild; times it was severe (once at the track with el-cheapo rotors) I jsut replaced the rotors.
Brakes off? Experience was mild front wheel/tire imbalance. A good spin balance has cured it.
Brakes on? My experience has been rotors warped or have some material transfer. Have tried some rotor resurfacing if it's mild; times it was severe (once at the track with el-cheapo rotors) I jsut replaced the rotors.
Brakes off? Experience was mild front wheel/tire imbalance. A good spin balance has cured it.
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From: northern california
A new possibility - my tie-rods got soaked with power steering fluid (just replaced my power steering unit which was leaking like a sieve) and became very loose, hence the vibrating front-end. Not to throw another wrench into your thinking, but check your power steering unit and see if there is a lot of fluid trapped in the front tie-rod boots.
