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Rear end shudder

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Old Jun 19, 2006 | 01:42 AM
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Rear end shudder

Maybe the limited slip dif. binding? when driving and making slow left turns and applying little gas the left side of my 8 shudders. Anyone else have this happen?

Last edited by Silver_Surfer; Jun 19, 2006 at 11:16 AM.
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Old Jun 20, 2006 | 08:03 AM
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I had this happen in a couple places in town where I had a sharp turn followed by hard acceleration. I just put in Tokico D-Spec shocks and the problem is gone now.
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Old Jun 20, 2006 | 08:11 AM
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Thats happened to me ever since I got the toyo-T1-R's I think the soft sidewalls are playing hell with my DSC. It sucks ***, I have turn DSC off to have it not happen. I would guess you are experiencing the same problem.
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Old Jun 21, 2006 | 02:59 AM
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Hmmmmmmm I'll give it a try
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Old Jun 21, 2006 | 11:26 AM
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Nope did'nt work. Calling Mazda, I hate those guys!
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Old Jun 24, 2006 | 03:15 AM
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They ordered me a new Dif.
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Old Jul 11, 2006 | 01:56 AM
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So it was a abnormality?

How slow of a left turn (MPH)? How bad was the shudder?
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Old Jul 11, 2006 | 10:12 AM
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Is this really abnormal?

My rear diff shutters when I first start to move making a hard left or right turn at low speeds (ie parking lots). I can coast through the same tight radius with no problem, it only occurs when I am first starting off under power. It actually seems smoother if I give it more gas and slip the clutch a little more. My own sense was that the slight clutch chatter with low rpm on gentle starts plays havoc with the torque sensor that tightens the rear diff. My Subaru STi behaved in exactly the same way.

Maybe yours is doing something much worse, but this did not seem strange to me with a torque sensing LSD on tight turns.
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Old Jul 12, 2006 | 02:08 AM
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Ahhhhh!! The smooothness
It was very abie-normal
Turns were at about 2-10mph very bad binding/shudders only when on the gas.
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Old Jul 12, 2006 | 10:33 PM
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I have an 05 GT with less than 4k and mine did it today. I backed into a parking spot and sat for a while. When I started to turn left out of the spot I felt a quik shake in the rear. It did once before but I didn't think to much about it until today. I hope there is nothing wrong.
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Old Jul 14, 2006 | 12:57 AM
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It happened to me today while taking a sharp u-turn in first gear at low speed. Are you sure this is abnormal? I'll talk to the dealer about it. But I'll have to duplicate it a few times before I go just to make sure.
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Old Jul 14, 2006 | 05:29 AM
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FWIW, I just changed to Royal Purple Max Gear 75w-90 in the rear diff and mine doesn't do this anymore. The oil that came out of the diff looked like gray puddle water. 4600 miles!!

Change the diff fluid and see how it does.

Overall, occasional binding is still probably "normal" for a torsen diff, unless you are experiencing something MUCH worse than I was.
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Old Jul 14, 2006 | 11:37 AM
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I thought about changing the rear end oil. I have Redline oils at home. But wanted the warranty to take care of this first because if the good oil would fix it now, what happens if it gave me trouble later after my warranty ran out?
The dealer replaced my dif, filled with dino oil(I asked) and its great now.


Now I'll change my rear end oil with the good stuff.

Last edited by Silver_Surfer; Jul 14, 2006 at 11:42 AM.
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Old Jul 14, 2006 | 12:20 PM
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Originally Posted by RX8Maine
Is this really abnormal?

My rear diff shutters when I first start to move making a hard left or right turn at low speeds (ie parking lots). I can coast through the same tight radius with no problem, it only occurs when I am first starting off under power. It actually seems smoother if I give it more gas and slip the clutch a little more.
Originally Posted by 1stgen8
I have an 05 GT with less than 4k and mine did it today. I backed into a parking spot and sat for a while. When I started to turn left out of the spot I felt a quik shake in the rear. It did once before but I didn't think to much about it until today. I hope there is nothing wrong.
both of you are describing the ABS self check.
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Old Jul 14, 2006 | 12:23 PM
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Originally Posted by Rinkadink
It happened to me today while taking a sharp u-turn in first gear at low speed. Are you sure this is abnormal? I'll talk to the dealer about it. But I'll have to duplicate it a few times before I go just to make sure.
you are describing what happens when the tcs control kicks in on a sharp turn. the LSD is trying to keep the reatr wheels at the same speed and the tcs hits the brake on one side- slowing that side and causing a shudder. that is normal and expected operation in that situation
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Old Jul 14, 2006 | 03:11 PM
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Originally Posted by Silver_Surfer
Now I'll change my rear end oil with the good stuff.
Break in the new diff for a couple thousand miles before the change. You'll get lots of metal shavings out of there by doing that.
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Old Jul 15, 2006 | 09:40 AM
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Makes sense!
















Last edited by Silver_Surfer; Jul 15, 2006 at 09:44 AM.
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Old Jul 17, 2006 | 10:05 PM
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Originally Posted by zoom44
you are describing what happens when the tcs control kicks in on a sharp turn. the LSD is trying to keep the rear wheels at the same speed and the tcs hits the brake on one side- slowing that side and causing a shudder. that is normal and expected operation in that situation
I get the same scenario on turning from a stop.
I have an AT sport.
Turned the DSC and TSC off to see if it makes a difference. None
Still shudders going left and going right from a stop on a sharp turn at low speed.
Took the Mazda Tech for a drive and finally something happened with him in the car. That was a first.
Showed him that it was doing it with the DSC/TSC on and with the DSC/TSC off.
Push and hold the DSC button down until swerving car light is on, on the dash.
He will call Mazda Technical tomorrow and ask them what is happening.
It does feel like the brakes are engaging.
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Old Jul 18, 2006 | 11:41 AM
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Originally Posted by Easy_E1
I get the same scenario on turning from a stop.
I have an AT sport.
Turned the DSC and TSC off to see if it makes a difference. None
Still shudders going left and going right from a stop on a sharp turn at low speed.
Took the Mazda Tech for a drive and finally something happened with him in the car. That was a first.
Showed him that it was doing it with the DSC/TSC on and with the DSC/TSC off.
Push and hold the DSC button down until swerving car light is on, on the dash.
He will call Mazda Technical tomorrow and ask them what is happening.
It does feel like the brakes are engaging.

Thats pretty much how mine was. Good luck!
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Old Jul 18, 2006 | 08:43 PM
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Well just got back from the dealership and they are going to put a new differential in on Friday.
The tech showed me the fluid out of the rear end and it was silver.
Showed me what he had wiped off the drain plug magnet,,A pile of metal about 1inch wide and 1/8 inch deep,some nasty stuff. Ground metal.
They changed the fluid in the diff.
The tech spoke to Mazda and they asked if I had aftermarket wheels.
Which I do ,told him to make sure they are the same size. (LOL)
Measure them they said.
Mazda asked if the DSC AND TSC were working ,,they are ,,did the tech test it with it on and off? Yes they did. Same thing with it on or off.
(So when both dash lights are on the systems are OFF.)
Mazda said install a new Differential.
Said the part would be in on friday the 22nd.
And we will see what happens with the new rear end.
I will update when the work is done.

Last edited by Easy_E1; Jul 18, 2006 at 08:46 PM.
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Old Jul 18, 2006 | 11:06 PM
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Be carefull after the dealership changes the dif. I nearly lossed it on a wet spot on the road while taking a turn! Felt like I got about 20hp on the low end.
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Old Jul 19, 2006 | 06:56 AM
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Originally Posted by Silver_Surfer
Be carefull after the dealership changes the dif. I nearly lossed it on a wet spot on the road while taking a turn! Felt like I got about 20hp on the low end.
Little less binding , drag on the rear end.
Good ,,,we will see what happens.
Oh and the car only has 4400 miles on it.
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Old Jul 20, 2006 | 10:46 PM
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Same problem

I have an 05 with 7900 miles. I have noticed this recently and it always seems to happen after I have been sitting for a minute...... just a quick shudder when starting out then after that, nothing.

Not a huge problem, and I am not sure I could duplicate it for a tech. Should I take it in or just change the fluid?

Opinions?
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Old Jul 22, 2006 | 02:22 PM
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I would at least have them look at the fluid.

And if you can duplicate the problem for the Tech that would be a bonus.
You might try driveing down the freeway for about 10 miles before you take it in to them. Then find a parking lot and do some turns from stopped.
Turn left then turn right, from going straight, also turn the steering wheel a half turn before you begin moving.
And dont take off to fast.
Good luck.

Last edited by Easy_E1; Jul 22, 2006 at 02:27 PM.
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Old Jul 22, 2006 | 04:27 PM
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Originally Posted by Easy_E1
I would at least have them look at the fluid.

And if you can duplicate the problem for the Tech that would be a bonus.
You might try driveing down the freeway for about 10 miles before you take it in to them. Then find a parking lot and do some turns from stopped.
Turn left then turn right, from going straight, also turn the steering wheel a half turn before you begin moving.
And dont take off to fast.
Good luck.
+1
Easy, Hows your 8 doing?
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