Rolling vibration around 20mph, ideas as to what it is?
05-28-2010, 11:04 PM
#1
1st Gear Member
Thread Starter
Join Date: Jan 2008
Posts: 143
Rolling vibration around 20mph, ideas as to what it is?
06 GT Vert with just exhaust and cia mods.
This has been happening for a while, but it just really got on my nerves the other day.
Around 20mph, when i am slowing down, i feel a vibration esp in the brake pedal. It's def something in the drive train that's turning because it comes and goes every little bit as i am slowing down and gets less and less until i stop. It makes the feeling with or without the brakes on. You can just feel it more in the pedal if the brakes are being used. So it's not rotors or anything. There is no jerking feeling like you would get with warped rotors only a vibration/grinding feeling as you slow down. The feeling is there when i swerve left and right around 20mph. There is no difference and it does not get worse or better when i swerve from side to side so its not a bearing. I had a buddy drive and he said he would put in new diff fluid and see if the feeling stops.
Anyone else have any ideas?
This has been happening for a while, but it just really got on my nerves the other day.
Around 20mph, when i am slowing down, i feel a vibration esp in the brake pedal. It's def something in the drive train that's turning because it comes and goes every little bit as i am slowing down and gets less and less until i stop. It makes the feeling with or without the brakes on. You can just feel it more in the pedal if the brakes are being used. So it's not rotors or anything. There is no jerking feeling like you would get with warped rotors only a vibration/grinding feeling as you slow down. The feeling is there when i swerve left and right around 20mph. There is no difference and it does not get worse or better when i swerve from side to side so its not a bearing. I had a buddy drive and he said he would put in new diff fluid and see if the feeling stops.
Anyone else have any ideas?
05-28-2010, 11:08 PM
#2
5th Gear Member
Join Date: Jun 2009
Location: Texas
Posts: 2,397
06 GT Vert with just exhaust and cia mods.
This has been happening for a while, but it just really got on my nerves the other day.
Around 20mph, when i am slowing down, i feel a vibration esp in the brake pedal. It's def something in the drive train that's turning because it comes and goes every little bit as i am slowing down and gets less and less until i stop. It makes the feeling with or without the brakes on. You can just feel it more in the pedal if the brakes are being used. So it's not rotors or anything. There is no jerking feeling like you would get with warped rotors only a vibration/grinding feeling as you slow down. The feeling is there when i swerve left and right around 20mph. There is no difference and it does not get worse or better when i swerve from side to side so its not a bearing. I had a buddy drive and he said he would put in new diff fluid and see if the feeling stops.
Anyone else have any ideas?
This has been happening for a while, but it just really got on my nerves the other day.
Around 20mph, when i am slowing down, i feel a vibration esp in the brake pedal. It's def something in the drive train that's turning because it comes and goes every little bit as i am slowing down and gets less and less until i stop. It makes the feeling with or without the brakes on. You can just feel it more in the pedal if the brakes are being used. So it's not rotors or anything. There is no jerking feeling like you would get with warped rotors only a vibration/grinding feeling as you slow down. The feeling is there when i swerve left and right around 20mph. There is no difference and it does not get worse or better when i swerve from side to side so its not a bearing. I had a buddy drive and he said he would put in new diff fluid and see if the feeling stops.
Anyone else have any ideas?
05-29-2010, 09:18 AM
#3
Cut & Paste Expert
Join Date: May 2007
Location: NW Arkansas
Posts: 13,322
Maybe the T-Loc is acting up?
If you change the 100,000 mile factory synthetic
rear end lube be sure to re-add the required amount
of friction modifier or the clutch packs will chatter
going around corners at low speeds.
If you change the 100,000 mile factory synthetic
rear end lube be sure to re-add the required amount
of friction modifier or the clutch packs will chatter
going around corners at low speeds.
05-29-2010, 01:29 PM
#4
5th Gear Member
Join Date: May 2005
Location: S.burbs Chicago
Posts: 4,793
I'm leaning towards a rotor issue. The pads are always touching the rotor even when not applied, so you could still be feeling this. And more when braking, as mentioned. If mostly in the pedal, and not the steering wheel, I would lean towards the rear rotors.
05-29-2010, 05:25 PM
#5
1st Gear Member
Thread Starter
Join Date: Jan 2008
Posts: 143
Well you feel it anywhere in the car. When I was riding with my buddy, I could feel and hear it. There is no jerking motion when stopping, its nice and smooth so I am almost 100% its not a rotor or brake issue.
05-30-2010, 11:47 AM
#8
Cut & Paste Expert
Join Date: May 2007
Location: NW Arkansas
Posts: 13,322
The bearing runout will always back the pads off of perfectly true
rotors after they are released by taking pressure off the brake pedal.
This is taking in to account that your floating caliper design is working
100% as it was designed to and not dragging in the slightest amount.
Add untrue rotors and the backing up of the pads effect is even more
dramatic.
If the pads always ran on the rotors, the heat would kill everything
pronto. Not to mention that the associated noise would be unbearable...
So if the pads are touching the rotor opposite of the pistion, I would
suspect dragging calipers.
Not saying its not happening but that it should not be happening...
05-30-2010, 12:01 PM
#9
5th Gear Member
Join Date: May 2005
Location: S.burbs Chicago
Posts: 4,793
eRepair, I loves it. lol.
I am far from a mechanic that's for sure, I would not even say alley mechanic, lol. I am just throwing out what I hear from customers when they bring their cars in, their complaints, and the cause and repair that's found by the technician.
I am pretty sure that the pads on most cars are actually just ever so slightly touching rotors, but I see what you are saying, and never thought about that. Try sliding a piece of paper between them suckers! Any brake inspection I have looked at, the pads are on the rotors. Now I believe this may be because the cars were pulled in the shop, lifted up, wheels pulled. And have not been rotated so no bearing "runout" has been seen.
Was just thinking about the brake sensor tab, when the pad wears to the sensor level, the sensor rubs on the rotor, making the squeal noise while driving along, no braking. This would indicate that the pad would also be slightly touching the rotor, as the sensor tab.
So I really don't agree or disagree after all I guess, I don't know, this is why I don't repair cars other than my own if its within my realm.
I am far from a mechanic that's for sure, I would not even say alley mechanic, lol. I am just throwing out what I hear from customers when they bring their cars in, their complaints, and the cause and repair that's found by the technician.
I am pretty sure that the pads on most cars are actually just ever so slightly touching rotors, but I see what you are saying, and never thought about that. Try sliding a piece of paper between them suckers! Any brake inspection I have looked at, the pads are on the rotors. Now I believe this may be because the cars were pulled in the shop, lifted up, wheels pulled. And have not been rotated so no bearing "runout" has been seen.
Was just thinking about the brake sensor tab, when the pad wears to the sensor level, the sensor rubs on the rotor, making the squeal noise while driving along, no braking. This would indicate that the pad would also be slightly touching the rotor, as the sensor tab.
So I really don't agree or disagree after all I guess, I don't know, this is why I don't repair cars other than my own if its within my realm.
05-31-2010, 09:59 AM
#10
Cut & Paste Expert
Join Date: May 2007
Location: NW Arkansas
Posts: 13,322
The spring is just that, a spring.
Pads are the associated backing plates rigid.
As the pads wear, the spring springs further and further
away from the rotor when the brakes are applied.
When the brakes are released, the springs are not released
as much as they were deflected when the brakes were applied.
Thats what causes the springs to chirp even when the brakes
are released. Not the pads dragging on the rotors.
Dragging pads are death to calipers, rotors and the actual brake fluid.
Pads are the associated backing plates rigid.
As the pads wear, the spring springs further and further
away from the rotor when the brakes are applied.
When the brakes are released, the springs are not released
as much as they were deflected when the brakes were applied.
Thats what causes the springs to chirp even when the brakes
are released. Not the pads dragging on the rotors.
Dragging pads are death to calipers, rotors and the actual brake fluid.