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Discussion Starter · #1 ·
I installed the Steeda Tri-Ax short throw shifter and added the Hurst stick and cue ball. I love the look and it works great however at higher RPM's near redline the shifter resonates at a pretty high frequency. I installed the thin rubber isolator that came with the shifter, that’s all. I’m not at those high revs very often but I don’t want this expensive car to do this. Has anyone else had this occurrence? Any lessons learned would be appreciated. I will begin my search for the cause this weekend.

thanks
 

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I installed the Steeda Tri-Ax short throw shifter and added the Hurst stick and cue ball. I love the look and it works great however at higher RPM's near redline the shifter resonates at a pretty high frequency. I installed the thin rubber isolator that came with the shifter, that’s all. I’m not at those high revs very often but I don’t want this expensive car to do this. Has anyone else had this occurrence? Any lessons learned would be appreciated. I will begin my search for the cause this weekend.

thanks


I don't have the Hurst stick but do have the Tri-ax short throw.I installed mine well over a year ago but have no issues.I think I used the original rubber that came on the GT 500.
 

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Lonnie there is a certain amount of vibration in the transmission which is transmitted through the shifter.
I'm thinking (out loud )that perhaps the difference might be in the solid plastic shifter ball or the rubber gasket..
The leather wrapped OEM ball might do a better job at absorbing the vibrations.

They also put the rubber gasket between the trans connection and the stalk to obviously minimize the transfer of these vibrations. Maybe you should take a look at that rubber gasket and see if a thicker one is needed. I think I will do the same and see if it makes any difference.
I did notice the other day an increase in vibration at 6000rpm. It would be nice to be able to reduce it somewhat.
 

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Discussion Starter · #4 ·
I was going to remove the Hurst Stick and install the standard Steeda stick and see how it responds. Does that big rubber block make the shifter mushy?
 

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Discussion Starter · #5 ·
Lonnie there is a certain amount of vibration in the transmission which is transmitted through the shifter.
I'm thinking (out loud )that perhaps the difference might be in the solid plastic shifter ball or the rubber gasket..
The leather wrapped OEM ball might do a better job at absorbing the vibrations.

They also put the rubber gasket between the trans connection and the stalk to obviously minimize the transfer of these vibrations. Maybe you should take a look at that rubber gasket and see if a thicker one is needed. I think I will do the same and see if it makes any difference.
I did notice the other day an increase in vibration at 6000rpm. It would be nice to be able to reduce it somewhat.
Thanks George
I think you're right about the OEM ball. It is damped more than the cue ball.
I'm thinking with the current set up the stick is matching the frequency of the tranny at high revs. a thicker rubber gasket may do the trick, or even a weight mass to change the natural freq.
 

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Thanks George
I think you're right about the OEM ball. It is damped more than the cue ball.
I'm thinking with the current set up the stick is matching the frequency of the tranny at high revs. a thicker rubber gasket may do the trick, or even a weight mass to change the natural freq.
Yeah I was thinking maybe a solid glass type cue ball would have been better.
 

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I have the FRPP ball shifter knob and handle installed on the stock shifter. It is bolted directly metal-to-metal to the shifter stub. I noticed that it transmits a high-pitched noise at cruise, especially in 4th through 6th gear. I can grab the ball and change the pitch or reduce the amplitude. Was thinking of putting a small piece of rubber between the handle and the shifter stub but have not done it yet. It is annoying so I just turn on the radio.
 

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Discussion Starter · #14 · (Edited)
I have the FRPP ball shifter knob and handle installed on the stock shifter. It is bolted directly metal-to-metal to the shifter stub. I noticed that it transmits a high-pitched noise at cruise, especially in 4th through 6th gear. I can grab the ball and change the pitch or reduce the amplitude. Was thinking of putting a small piece of rubber between the handle and the shifter stub but have not done it yet. It is annoying so I just turn on the radio.
I installed the thin rubber isolator that came with the Steeda shifter. The frequency is excited at around 4800rpm and takes off at 5K, all other modes it is fine.

I'm not sure I want to dampen the stick any more than it is, I like the way it feels. I don't want to make it mushy. I may play around with different masses to move the response above the generating frequency.
 

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I installed the thin rubber isolator that came with the Steeda shifter. The frequency is excited at around 4800rpm and takes off at 5K, all other modes it is fine.

I'm not sure I want to dampen the stick any more than it is, I like the way it feels. I don't want to make it mushy. I may play around with different masses to move the response above the generating frequency.
Thx for the update. Now in plain English please. This somewhat average techie is just not quite sure what your expressing. So the rubber isolator is minimizing the noise to certain rpm ranges. I'm wondering why all others with the tri-ax haven't mentioned this before.
 

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Discussion Starter · #16 ·
Thx for the update. Now in plain English please. This somewhat average techie is just not quite sure what your expressing. So the rubber isolator is minimizing the noise to certain rpm ranges. I'm wondering why all others with the tri-ax haven't mentioned this before.
I think they have
The thin rubber isolator will dampen or lesson the vibration or noise.
The Steeda Tri-Ax shifter alone (with the stock boot and shifter knob) does not sing at the annoying levels like the Steeda Tri-ax with the Hurst set up I have. The assembly is not dampened as well and is a lighter mass. I have heard of others mentioning this vibration but IMO most are living with it.

The tranny at the higher rpm range starting at about 4800 (for mine) matches the natural frequency of the shifter with the plastic ball on the end. It is like a tuning fork. The result is the stick vibrates and it vibrates at a high enough frequency that is sings.

There are 2 basic ways to stop it from vibrating
1. Isolate it...Add rubber to dampen or stop the vibration. This is similar to putting your hand on the ball to make it stop. My issue with adding a thicker rubber isolator is that the spring rate of the rubber will soften the stick or make it mushy. I like the good firm positive shift.
2. Change its natural frequency. Add or remove weight to change or move or tune the stick away from the tranny freq that is making it sing.
The preferred direction would be to tune the stick to a higher frequency, say around 6200 RPMs (somewhere my car should never see)

Desired result
No stick buzz at any normal operating range
 

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LOL
That would be my preference George

I got my dynamics guy on it
he loves making vibrations go away
I could use him up here for mine too plus I have a header pipe touching the steering shaft and that is sending vibrations into the steering wheel too.:flame:
 

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I think they have
The thin rubber isolator will dampen or lesson the vibration or noise.
The Steeda Tri-Ax shifter alone (with the stock boot and shifter knob) does not sing at the annoying levels like the Steeda Tri-ax with the Hurst set up I have. The assembly is not dampened as well and is a lighter mass. I have heard of others mentioning this vibration but IMO most are living with it.

The tranny at the higher rpm range starting at about 4800 (for mine) matches the natural frequency of the shifter with the plastic ball on the end. It is like a tuning fork. The result is the stick vibrates and it vibrates at a high enough frequency that is sings.

There are 2 basic ways to stop it from vibrating
1. Isolate it...Add rubber to dampen or stop the vibration. This is similar to putting your hand on the ball to make it stop. My issue with adding a thicker rubber isolator is that the spring rate of the rubber will soften the stick or make it mushy. I like the good firm positive shift.
2. Change its natural frequency. Add or remove weight to change or move or tune the stick away from the tranny freq that is making it sing.
The preferred direction would be to tune the stick to a higher frequency, say around 6200 RPMs (somewhere my car should never see)

Desired result
No stick buzz at any normal operating range
Thx, alot clearer, but how do you re-tune to a higher freq? :ack:
 

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I have the Steeda shifter which I put a Hurst chrome handle and white ball on and I don’t have any vibration problems. My Hurst handle it not the one that comes with a shifter for a Mustang GT however… this was one of my first mods and it was right after B&M bought Hurst and no one could give me the part number for the Mustang GT handle, so I just bought the shortest straight chrome handle they had, and then I cut it down even further which I think now makes it shorter than the Mustang GT handle… I wonder if that raised its frequency to a much higher RPM range, thus no noise. I do not have any dampener between the Steeda stub and the chrome Hurst handle… just metal to metal, thus very solid shifts
 

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Discussion Starter · #20 ·
I have the Steeda shifter which I put a Hurst chrome handle and white ball on and I don’t have any vibration problems. My Hurst handle it not the one that comes with a shifter for a Mustang GT however… this was one of my first mods and it was right after B&M bought Hurst and no one could give me the part number for the Mustang GT handle, so I just bought the shortest straight chrome handle they had, and then I cut it down even further which I think now makes it shorter than the Mustang GT handle… I wonder if that raised its frequency to a much higher RPM range, thus no noise. I do not have any dampener between the Steeda stub and the chrome Hurst handle… just metal to metal, thus very solid shifts
I think you are right. I may remove the rubber gasket and go metal to metal. If your comonation of stick and ball is lighter than the one I have it would raise the freq. above the RPM I'm seeing the buzz. I'm going to put an acelerometer on the stick and drive the car to see what freq it's resonating at. I don't think it will take much to eleminate the problem.
thanks for your input.
 
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