need help from an experienced rx8 owner! rattling noise while accelerating
 

ok guys heres my problem and yes i have done hours of searching and reading posts. and cant seem to find a solution.

the noise sounds like a rattle or grinding under the gearbox, and its only under accelerating, the sound is at low rpms it starts around 3000 and you cant hear it after 4000rpm. it seems to happen in all gears and only if im cruising and then give it some gas. it is more noticable when you hit 3rd gear and higher when there is more of a load on the car. the noise is starting to worry me and im wondering if anyone has found a solution for this issue.. it doesnt make a difference if it is cold or hot, the noise is not there when the car is not in gear or when you rev it in neutral. it also is not the converter, is there any bearing in there or a clutch issue that would make this noise happen..?? thanks in advance

the car is a 2004 rx8 gt 6 speed 51,000 km, all stock, compression is good and plugs were replaced a while ago. and always run supreme gas

When was the last time the tranny fluid was changed?

You say it's "under" the gear box. Do you mean under the shifter? Gear box is really your transmission and there's nothing but maybe a heat shield under your transmission.

Having said that, I'm going to assume you mean the shifter. If so, there is a bolt and another piece that keeps the shifter solidified in place and keeps it in gear. If this comes loose, it can cause your shifter to vibrate in all gears and in idle, and especially while shifting.

A good test is while the car is not running and in neutral, can you feel any play in the shifter. Especially see if you can lift up on it at all. I don't mean play back and forth (left/right/fwd/bkwd), but up and down (lifting and pushing down). If you feel any play there at all, that brace is probably loose and you need to tear it down and tighten it or replace the brace that keeps it tightened down.

Good luck!

also, what makes you think that it isn't the cat, because it could be your cat's heat shield coming loose.

Thanks for te reply Guys. I really appreciate it. As for the gear box part. Yes I ment the shifter. The noise is Coming right under it. The noise seems to start well where I can really notice it in 3rd gear. Can't hear it in 1st or 2nd. And I can't hear it at all after 4000rpm. The trans fluid I'm getting it checked today and I don't believe it has ever been changed seeing how the car only has 50,000 km. The is also no play in the shifter. Just down and that's for the reverse gear. There's no play pulling up. And I'm not totally sure it's not the cat. I just figured since I can't hear it al all when the car is not moving and I rev it. It's only when its in gear Which makes me think it might be clutch or trans related.

Ok just got home from the shop. Trans fluid is full and looks to be very new. Same as the rear end. Checked the exhaust and the cat is good and all the heat shields are not loose or rattling. There is a small leak in the exhaust and it is coming from a gasket on the manifold. Also I forgot to mention there is a after market clutch on it. It's a f1 stage 2 clutch that was installed about 2000km ago from the previous owner.

Did you ever find a solution to this?
My 8 seems to be doing the same, right at 3k rpm

Can you give more clarification as to where this brace/bolt is? I'd love to get my shifter to stop shaking all over the dang place.

I have the same exact problem and it bugs the hell out of me. Please if anyone found a solution, please help a brother out. I'm looking everywhere to no avail!

Mine was heat shield coming lose. After repairing that the noise is gone.

it could be an exhaust rattle or it could be from normal wear and tear inside the transmission, at lower speeds a worn transmission will make a rotating rattle sound like a low growl and go away at about 3.5k. 5th gear is direct and should be quiet if it is in fact the tranny, 6th is usually quiet as well but it's usually heard in 2nd through 4th.

if it is the transmission it's usually a sign of abuse or excessive miles which have worn the main bearings. it also does not mean the transmission is about to give out, but just an annoyance.

Get some stainless steel zip ties (I found them at Menards in the electrical section) and wrap them around the heat shields. A loose one will make a racket. There are heat shields around the header and the cat. Once they rust a little, the spot welds that hold the top and bottom halves together break. You might have to connect two zip ties in series to get around the heat shields.

Oh, and wait for the car to cool off so you don't burn yourself :wink2:

Hey guys. So for some reason it's saying I can't post a new thread because The site is saying I haven't activated my account or I don't have permission? I don't know why... But anyways I got a brand new aftermarket clutch installed when mazda did a warranty on the engine. Now the clutch makes a popping sound whenever I push down the clutch at about 90% depth. It also makes a metallic vibration sound in gears 4,5,6 ONLY when I'm super lower rpms, between 1,500-3,000. Of course mazda doesn't want to take responsibility for it because they're blamed the third party clutch. And the shop where I bought the clutch is saying it's workmanship error and they didn't install it. So this might cost me $600 just for mazda to drop the tranny and say nothings wrong when their is..

Sounds like some people had some similar problems above, minus it now being the higher gears and the clutch pop.

So anybody come across this before and could explain the clutch popping while being pressed in and the metal on metal vibration sound in the lower rpms in those specific gears??

Thanks!

2nd and 4rth problems
 

ok so to start this off i got a mazda rx8 2005 shinka. so say if im driving normal shifting around 3-4 rpm's, my 8 shifts fine but lets say im racing someone or i just get on the gass hard my second gear and my forth gear grinds every time iv tried double clutching and still nothing so lets say i star in first and i slam rev limitor then go to second it grinds same thing when i go from 3rd to 4th. it will only let me in 2nd/4th gear if i hold the clutch till rpms drop under 2 rpm's

synchros, common problem. next time try searching

"spin the tin-can tranny noise"
 

I am having this exact same problem and it is not a light rattle (sounds like a rapidly "clanking" metal in a direct proportion to the rpm and load) , it is loud, only occurs when in gear at around 3000-4000 rpm.

Same issue, but why?
 

So, I have an 09 R3 and replaced the clutch at the dealer and now when accelerating under load at low rpm say 3k-4k there is a vibrating noise and I can't source it. I need help in this matter. Because it never used to make this vibrating noise, ever! Thanks

I would ask this question to the dealer first. They warranty their work, even if we figure out the problem here, we can't fix it for free.

I would guess something wasn't installed quite right during the clutch job.

09 R3 new clutch noise when accelerating
 

Roger that thank you. I'll do that. Thanks.