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Discussion Starter #1
Hey guys,
I bought a B&M SS a few weeks back and installed it the first day I got it, without installing dynamat. 2 days ago I took apart the shifter and put dynamat around the base of the shifter and the metal bracket/plate that holds the rubber piece around the base of the shifter and i put a little grease where the shifter engages and in the ball joint inside the shifter. After doing all this to "sound dampen" I ended up with a louder transmission whine... wtf? I have a MOMO knob and it uses a rubber cap on the top of the shifter so I know thats not the problem... my only thought is that this time i tightened all the screws/ bolts tighter which allows the sound to travel better through the pieces? I dont know why its doing this.
For the guys out there with Ralco's, how's the trany whine? I'd be interested to know if this quieter, worse or on the same level as the B&M
 

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Haven't heard the B&M to be honest with you. I have the Ralco and also put Dynomat around the shifter...the only whines I hear is coming from 5th gear. Really minimal. Other than that, I really enjoy the shifter. So in all theory, I can't really justify the B&M to the Ralco but, I can tell you that mines is not as loud as you make yours seem to be.
 

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you might hate to hear it but what you need is a counter weight shift knob!!! i got the greddy and problem fixed! might not want to give up your momo but if you dont want the whine you know what you have to do. GL!
 

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Discussion Starter #4
you might hate to hear it but what you need is a counter weight shift knob!!! i got the greddy and problem fixed! might not want to give up your momo but if you dont want the whine you know what you have to do. GL!
You think that might be causing the problem? Cause the momo comes with a rubber cap you put over the threading to fits snuggly into the shifter. To me, it feels like its coming from where the shifter engages the tranny, like that plastic piece needs to be improved. I used the one from the stock shifter like the threads recommended, but I dont know what else can be done about it...
 

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I have B&M SS also but i've got used to it. Here is my theory for what causes the noise.

The shifter rod (with the white ball at the end) is engaging to the tranny and vibrates to the output rpm of whichever gear youre on. The shifter flange is bolted to the tranny housing which connects to the engine, so it vibrates at the engine rpm. If you notice, there is a different sound pitch at different gear but it's totally quiet on 4th gear. That's because 4th gear is 1:1 so there is no frequency and phase difference between the engine and the tran. In other word they vibrate in harmony. When the 2 run at different rpms, the shifter and the flange bang against each other and that tranlates to all the noise that you hear. Why doesn't the OEM shifter make the same noise? I noticed that the stock shifter assembly is quite heavy when I took it off, which makes me believe that it's made of steel which is more damp than aluminum that is used on the B&M. Also I'm sure that the oem design is much more complicated with layers of damping material inside the shift rod rather than just a solid rod like all aftermarket products.

Wrapping sound absorbing material around the shifter is not the best way to tackle the problem. There was a thread on this topic about 1-2 years ago saying that you should put some energy absorbing rubber (E.A.R) between the shifter flange and the tranny housing and under the screw heads. What this does is knock down the vibration amplitude of the flange so it bangs against the rod less. As an ME I think this makes a lot of sense although I never tried it out. I opted for the easy solution instead: loud music.
 

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The MOMO knob having that rubber cap doesn't mean anything, as you still have the three metal set screws tightened directly to the metal shifter. I have the B&M shifter as well. I've had many MOMO knobs in the past but not on my IS. Right now I have the small TRD leather looking ball shift knob and I don't consider the whine to be too bad. buister has a good idea how to isolate the whine as much as possible. Otherwise, I think my TRD with it's plastic threads and plastic/rubber construction would transfer less noise than a MOMO knob. The Greddy counterweighted knob may work even better. I'm thinking about trying it, or the TRD duracon.
 

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Discussion Starter #7
Thanks for chiming in guys, appreciate your opinions. I'll have to try and find some E.A.R. cause I love this shifter and I'm not gunna get rid of it, but I still want that nice quiet lexus sound... until I get boost, and let all hell break loose.
+rep to all who responded
 

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I've been wanting to fix this problem too, it drives me nuts!
 

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You neg repped me! No big deal, just funny.
 

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