I purchased my 01 coupe 6 speed with 114k miles a little over a month ago and about 2 weeks ago replaced the trans with one out of a 98 model with supposedly 60k miles because of a 4th gear grind, and did a trans and rear diff fluid change at that time. I think I believe this sound to have been there before the trans swap, but I never really payed attention to it until someone rode with me the other day and pointed it out because it isn't very loud and I figured it was probably normal like a throw out bearing noise.

Anyway, today while driving I did a little test and the sound seems to be coming from up under the shifter, or even a little further forward. But definitely does not sound like the sound is coming from behind the driver seat, though I know sounds can travel through the torque tube.

I notice it in all forward gears except 4th while accelerating or constant speed on the gas, goes away when not on the gas and also goes way when I push in the clutch. I will do some more testing to make sure it is completely gone in 4th. I have not tested reverse yet.

I used regular non synthetic valvoline atf in the trans because I read of the paper blocker rings that could be in the 98 trans, and used royal purple synthetic diff fluid in the rear diff that already had the friction modifier in it, should I add more to it?

I hope to take a video of the sound soon so you guys will know exactly what I am talking about. Everything works fine, the sound is just kind of annoying now that I know it is there and think about it, and worries me that it seems to go away in 4th knowing I just did all that work to replace the tranny. Is this something serious that needs attention or could I just let it ride and deal with the sound as long as nothing is going to fail? I hope to do an off road x pipe soon so maybe that will tune out the buzzing noise and ill no longer notice it

 

Is the shifter sound deadening mat in place?! There is supposed to be a rubber mat covering the shifter box if it is missing you will not believe the noises coming from there!!!

 

Yes I remember putting it back in place when I hooked the shifter back up to the new transmission.

 

Check the bushings on the shifter box, that's where my noise was coming from. Does the noise go away if you keep your hand on the shifter while your accelerating? If you need new bushings zip has poly-urethane ones for about 20 bucks.

 

I have this same exact sound as you. I checked my sound dampening material as mentioned in this thread and everything was in place, I added some dynamat around the shifter and passenger compartment and it didn't help at all.

I recently changed my Trans and diff fluid and used the anti-slip and it didn't make a different in the noise level.

It sounds like the differential to me... I have a RPM stage 3 differential with less than 20,000 miles on it. I would hate to have to have it rebuilt again ...

Please let me know if you find out what it is.

 

Pretty sure it's your shifter vibrating. Take out you console and make sure everything is snugged up and everything is in place and properly aligned. After a couple of times, you'l have the console out in 10 minutes.

 

Can you give me some more details about this please? What exactly is the "console", like do you remove the trim around the shifter and under the shift boot where it exposes the torque tube and re align the shifter? (I've done that and it didn't help), or do I need to remove the radio bezel trim, remove the radio, and try to get back there?

I've never heard of removing the console, could you please explain exactly what needs to be done? I really appreciate the help!!! it's been driving me crazy.

 

If you do a search on replacing the shifter, there are some really good pictures of the process. Basically it's just removing a few screws to remove the gauge frame, ashtray, and center console. This exposes the shifter, which has four screws holding it in place. Make sure that all of the screws are snugged up and the gaskets are in place. I don't have the pics handy, but a quick search of shifter replacement in C5 Tech will get you what you need.

 

I doubt it's the shifter or shifter box, I took the console out and aligned and tightened the shifter twice. Also it does not go away with my hand on the ****. It does go away in 4th gear, so basically has to be in the trans or diff I would think. I was hoping it could be a torque tube bushing or something but doesn't seem likEly now that I've for sure noticed it only goes away in 4th gear. I don't think it's hurting anything to drive it like this everything seems fine, it's just annoying