After my last track day I've noticed that my transmission is rather noisey when I leave it in neutral (clutch out). Sort of a "ggrrrrrrrrrrrrrrrr" sound.

Does anyone think this means a pending tranny failure? Should I worry about it? The car still drives fine but I don't want to get stranded with a tranny failure at my next track day.

-John

 

There is a great transmission troubleshooter on Mazdatrix website that desribes all the sounds and thier associated causes. Check it out www.mazdatrix.com

 

Sounds like a noisy throw out bearing.

 

^^^yep, mine growls like an angry dog but it doesn't affect drivability so I'm just gonna wait until I need to replace the clutch.

 

couple of mine did that. input shaft bearing is going. sounds like a washing machine with some nuts and bolts thrown in it

 

Vosko is correct. When the clutch is not engaged, the throw out bearing usually makes no noise - even if it is bad. The throw out bearing is a thrust bearing that engages as the pedal is pressed. That is when it should make noise. The main input shaft coming from the engine is the only shaft spinning since in neutral all of the other gears are stationary as well as the output shaft. With it disconnected from intermediate shafts, the bearing play is evident by the noise and will allow the shaft to move sideways slightly. Once coupled up with an intermediate shaft, the play is eliminated and the noise lessens (but still noticeable, especially later on) Waiting too long to change the bearings will cause uneven wear on the cones and gears. Better get another tranny soon or rebuild yours.

Tim

 

Once it's warmed up, my trans has made a light rattling sound in neutral for as long as I've had it, and I bought it new in April 1992.

 

Yep its the input shaft. Did you shift from 3rd to 2nd by accident...JK

Change the oil to some nice 75w redline or a similar high grade synthectic and see how much metal comes out when you drain the old oil. The trans will be fine for a while so just wait until you have some down time and look for a good used trans in the mean time.

 

Thanks for your advice everyone... my Miata transmission has been super noisey for the last 30k miles and is still holding up... I suppose I'll just wait until this one blows... I don't want to rebuild it just of a little noise.

No... no accidental shifts from 3rd to 2nd... that I'm aware of! Although I did grind the gears by accident pretty good a couple of times goint to 3rd from 2nd... oops.

-John

 

Mine made a similar noise a few weeks ago at a fast down shift from 4th to 3rd, but mine ended up being a broken counter shaft which proceeded to take out about everything else that I just had put in the tranny when I broke the output shaft 2x last year at the drag strip....New tranny's on the way! Anyone need a boat anchor?

Art

 

This happened to me with my FC, but I found out the hard way that it wasn't the tranny or the bearing. I Switched 2 trannys over in one night. I was pissed when I found out what was really making the noise. The damn flywheel nut was loose. Not loose as in you can move it with your hands, but loose enough that I didn't need a breaker bar. I just needed my body weight to loosein it. (needs 360ftlbs.)

So Both my and my friend tighted with the breaker bar. Put everything back together that night, and started it up and it was fixed.

The noise that I was getting was like metal clapping. It sounded like the driveshaft was bouncing around in the input hole.(ie messed up bearing.)

All I am trying to point out is another part you should consider. Everyone on the forum told me it was the bearing. You just gotta try **** out for yourself I guess to find the problem.

Good luck.

 

Fritz, John, and Art: my transmission was making this noise once the new motor was installed @ Rx7 Store. This noise was faint the last time Rx7 Store installed the KDR motor (18000 miles ago). With the new rebuild, the transmission was much louder, especially in neutral, 1st, and 2nd gear. I also get an intermittent clicking hoise in 5th gear when modulating the throttle, while on the interstate. So is it the input shaft bearing, or a loose flywheel nut? FWIW, my transmission has 122,000 miles on it. I have both the ETB and rear diff brace installed. Did these braces wear out my transmission input shaft/counter shaft prematurely?

 

How many miles on your transmission?