Transmission Noise in Neutral @ Cold Start

[Ultramaroon]

Originally Posted by pantdino

It is very unlikely to be the TO bearing, which is only under load when the clutch is pushed in.

My TR6 tranny was way noisy and got quieter when I pushed the clutch in. It was the input shaft bearings.

Re the gearbox viscosity issue-- the viscosity decreases as it warms up, so using a higher viscosity oil would likely make the noise worse, not better. When the clutch is engaged all the gears are spinning in the gearbox but just not engaged. So it will make some noise

This is an internal adjustment/shimming issue. It's a little more than normal chatter but by itself is not a big deal.

I know it's not the TB but there's conflicting opinion so I offered a solution to rule it out. Just hanging out for now.

[MisterSheep]

Just noticed this noise too the morning after I switched to Motul 300. Same exact thing. Horrible chatter noise that goes away when clutch is engaged. It didnt happen when I had the stock trans fuild

[nickg]

Originally Posted by MisterSheep

Just noticed this noise too the morning after I switched to Motul 300. Same exact thing. Horrible chatter noise that goes away when clutch is engaged. It didnt happen when I had the stock trans fuild

I switched last weekend and I'm experiencing the same thing. It happens in from idle to about 2k. Most days it will go away after it has warmed up, but yesterday afternoon it was persistent. Also, I do mostly short distance city driving so I doubt my transmission is ever fully warm

[86Tony]

See thats why i tell people now to not use motul or what ever tranny fluid. Its not like most guys track there cars that hard to need motul. I use oem on track after i got new tranny and its fine. So for new fellow 86 owners that read this i would refrain on using other stuff then oem. Not sayin it will happen to everyone but what i seen so far there quite abit of us that encounter this issue after switching fluids.

Sent from my SM-N920W8 using Tapatalk

[MisterSheep]

Originally Posted by nickg

I switched last weekend and I'm experiencing the same thing. It happens in from idle to about 2k. Most days it will go away after it has warmed up, but yesterday afternoon it was persistent. Also, I do mostly short distance city driving so I doubt my transmission is ever fully warm

Is this just a common problem with switching to Motul? I wonder if anyone has just ignored this and what happened.

[86Tony]

Originally Posted by MisterSheep

Is this just a common problem with switching to Motul? I wonder if anyone has just ignored this and what happened.

Yes i really think its the motul if you search up about this through out the forums, the people that had this issue was the one that swap to motul including myself. Also when i ask my dealer to look at this problem for warrenty they call me and first thing they ask me if i changed my tranny oil , Of course i said no but that just rang a bell through my head and got me thinking that it had to be fluid related or else why would they ask me that question in the first place.

[strat61caster]

Originally Posted by MisterSheep

Is this just a common problem with switching to Motul? I wonder if anyone has just ignored this and what happened.

No, the throwout bearing causing the noise has no direct interaction with the transmission fluid. Unless you are making the argument that the international standard for transmission fluid specified by Aisan is deficient as it causes a mechanical impact on the transmission input shaft affecting the throwout bearing.

Motul 300 meets the specifications in the owners manual, most cars have not changed transmission fluid at this point as it is a 60,000 mile service.

This video shows the assembly on a VW, the parts and motion are a bit different in an 86 but the fundamentals are identical: (I don't think you need to watch the whole video of him replacing it, just enough to understand what is making noise and where it's located)
[ame="https://www.youtube.com/watch?v=5qpUr-NnR2o"]Overview of 5-Speed Clutch Lever & Throwout bearing system - YouTube[/ame]


This video shows a worn out throwout bearing, as it gets beat up from being used (they wear out without abuse, wear faster with abuse) it gets sloppy and begins to rattle around.
[ame="https://www.youtube.com/watch?v=L3SloMlvvHw"]Mitsubishi L200 rattle from clutch release bearing - YouTube[/ame]


This is common across all makes and models, but quality parts should make it to at least 60k miles no problem, my FR-S throwout bearing is audible under most conditions at 43k miles (Yes switched to Motul 300 at 30k). I'm a bit disappointed but I've put it under some rough conditions (couple hours spent tracking and autocrossing the car so far not to mention the occasional spirited drive on public roads) so fingers crossed that it makes it to 60k before I replace it, it sounds like the clutch itself is solid so maybe I'll just be doing the bearing which should be like a $20 part at the most.

[nickg]

Are you sure it's the throwout bearing? My car only has 12k miles and the sound only started right after I changed the fluid, although today it went away quick

Sent from my XT1575 using Tapatalk

[86Tony]

Originally Posted by nickg

Are you sure it's the throwout bearing? My car only has 12k miles and the sound only started right after I changed the fluid, although today it went away quick

Sent from my XT1575 using Tapatalk

Ya i changed my fluid when i had 3000 miles on it, and that noise occured now im almsot at 20k with 5 track days on it and still have that noise. if it were the throwout bearin it be long gone already

[strat61caster]

Originally Posted by nickg

But when the clutch pedal is depressed the input shaft would stop spinning, and since the noise happens at a stop the output shaft would not be spinning either. Since the noise only happens when the clutch is engaged (gears in the transmission spinning), it leads me to believe that the problem is in the transmission.

Believe what you will, good luck finding a solution.

[gonzagnr]

did someone finally find out what the noise was?
i do not own a GT86, but i own a suzuki swift sport zc32s, which has an aisin 6MT, idles at 600rpm, and has the same rattle, under same circumstances as the Gt86.
Dealer replaced clutch, CSC (hydraulic TOB), and plate, and noise still the same.
car comes with single mass flywheel, and idle is a bit rough at 600rpm, so in my opinion it has to be some vibration traveling towards the gearbox, producing some king of gear backlash.
if i turn AC on, idle speed goes up to 700rpm, and there is no more noise.
shifting is perfect while driving.
but the symphtoms are 100% the same as the GT86, even if i give a small blip to the gas like the guy in the original video, there is some variation for a moment in the rattle, and then as the rpm goes above 600, no more noise.
or if i lug the engine, there is a minimal rattle, and as soon as car is at 1mph, no more noise.
the only thing i have noticed, and i have not seen anybody on this forum comenting about that, is that when the car is rattling at idle, if i move the gear lever to 3rd or 4th position without pressing the clutch, if i hold it there, the noise disappears.
i have seen many people with swift sport listening to the noise (on the other hand others say they dont hear anything), i also spoke with a guy that had his clutch replaced, but also the bearings of the gearbox replaced, and no improvement.
as far as i know, nobody had its tranny replaced because of this.
in any case, sorry for bumping such an old thread, but i just wanted to share a similar experience, on an also aisin 6MT gearbox, from a car idling at 600rpm.

[StraightOuttaCanadaEh]

I owned a Mini Cooper and it did this as long as it was cold. It was flywheel chatter. After I replaced the flywheel, it wasn't as loud but it was still there a bit. I just lived with it and looked at it as normal noise.

[Andyxin]

Any updates? I got this noise too after switching to motul gear300 few days ago.

[007BRZ]

Originally Posted by smbstyle

it seems to be a noisy throw out bearing or pilot bearing; should be an easy fix.

Would not be the TOB if the clutch is depress in, but could be the pilot bearing since the shaft is turning in neutral with the clutch out