Trans whine?

[Stang70Fastback]

Originally Posted by Spartarus

If you are rolling in gear, the input shaft will be moving at the same speed, regardless of whether the clutch is in or out.

from neutral to in-gear, there will be a spin-up noise if you have bearing or synchro issues. The only time the input shaft will "spin up" is going from an extended roll in neutral to being in-gear, or rolling from a dead stop. Otherwise, it will always be spinning.

I think perhaps I wasn't fully clear in my explanation, though it's possible I'm still misunderstanding something, as I'm not yet an expert in these things. As I understand it, if my car is sitting still, clutch OUT (not depressed), with the transmission in neutral, the input shaft will be spinning along with the engine. If I clutch in, this disconnects the engine from the input shaft, and it stops spinning. If I then release the clutch, the engine is again reconnected, and the input shaft spins up again.

In my case, I hear the whine when the car is sitting, clutch out, in neutral. I press the clutch, and the sound goes away. I release the clutch, and the sound "spins up" along with the input shaft.

Also, when I shift from 1st to 2nd, the input shaft abruptly goes from spinning at 5k to spinning at 3k RPM. I can HEAR this in the form of that whine abruptly spinning down in a similar fashion as I push the gear shifter into second.

If there is a "spin up" noise from clutch-in to clutch-out regardless of whether you are in gear, I can explain that phenomenon based on a nearly seized throwout bearing, as it begins to spin in relation to the clutch fingers, dragging against them because the minimal preload is insufficient to keep a dying bearing spinning, but the preload is sufficient to create noise against the clutch fingers. That theory can be confirmed easily; pull the trans and look at the TOB.

Otherwise, gear whine under load is usually not bearing related. It is usually related to gear alignment. If you have worn out some of the tolerances in the transmission under hard driving, whining will start to emerge. It is not necessarily a bad thing, as it doesn't necessarily indicate harm being done, just an increase in gear lash, or decrease in bearing preload. Problems of helical gears. Internal bearings going bad in a transmission don't whine. They sound like a blender full of nails.

Unfortunately, I am not in a position to easily pull the transmission (in fact, I've never done that before.) What you are saying makes sense, but I would think that I would get at least some sort of noise with the clutch depressed, if the throw-out bearing was failing, no?

Also, if it's the latter, then that makes sense too, and I'd be totally okay with it if it's just a result of the transmission being "broken in", but as I said, I doubt it is a case of gear whine, as the sound appears to be independent of the actual gears in the transmission.

[humfrz]

Originally Posted by Ultramaroon

Hey, how about we completely disassemble and inspect both your and my transmissions. Then we can compare differences.

.......but......but...... but, that wouldn't be scientific.

The experiment requires a "control" i.e. a NEW transmission.

However, you bring up a good point ...... the experiment does need some replication ....... so, @Stang70Fastback @MisterSheep @HachiRo will you step up and offer to disassemble your transmissions for the experiment ...... ??




humfrz

[HachiRo]

Originally Posted by humfrz

.......but......but...... but, that wouldn't be scientific.

The experiment requires a "control" i.e. a NEW transmission.

However, you bring up a good point ...... the experiment does need some replication ....... so, @Stang70Fastback @MisterSheep @HachiRo will you step up and offer to disassemble your transmissions for the experiment ...... ??




humfrz

My only car and I live in a 4-plex with little work room haha.

I know they were selling an FRS engine for about 2 grand or something dirt cheap on the FB classifieds page in case anyone wants a backup.

[Spartarus]

Originally Posted by Stang70Fastback

I think perhaps I wasn't fully clear in my explanation, though it's possible I'm still misunderstanding something, as I'm not yet an expert in these things. As I understand it, if my car is sitting still, clutch OUT (not depressed), with the transmission in neutral, the input shaft will be spinning along with the engine. If I clutch in, this disconnects the engine from the input shaft, and it stops spinning. If I then release the clutch, the engine is again reconnected, and the input shaft spins up again.

Correct.

In my case, I hear the whine when the car is sitting, clutch out, in neutral. I press the clutch, and the sound goes away. I release the clutch, and the sound "spins up" along with the input shaft.

That also just happens to coincide with loading and unloading the throwout bearing. How long does this "spin up" take? The input shaft will go from stop to engine RPM in a fraction of the clutch travel. It should be nearly instantaneous. If it takes longer than that, it is not the input shaft you are hearing. That does not necessarily rule out an internal transmission issue, but it rules out the input shaft bearing.

Also, when I shift from 1st to 2nd, the input shaft abruptly goes from spinning at 5k to spinning at 3k RPM. I can HEAR this in the form of that whine abruptly spinning down in a similar fashion as I push the gear shifter into second.

Now, you said that the noise goes away clutch-in. You presumably have the clutch in when you are shifting...? So describe this a little better... Does the noise suddenly come back? but only during the shift? Because that points to another problem entirely.



Unfortunately, I am not in a position to easily pull the transmission (in fact, I've never done that before.) What you are saying makes sense, but I would think that I would get at least some sort of noise with the clutch depressed, if the throw-out bearing was failing, no?

Not necessarily. Adding a thrust load to a worn or failing bearing can silence it, for largely the same reason that pushing on a loose, rattling panel can stop the noise it's making. In fact, most people reporting TOB issues say the noise starts clutch-out after cold start, and only progresses to happening clutch-in when it gets really bad.

Also, if it's the latter, then that makes sense too, and I'd be totally okay with it if it's just a result of the transmission being "broken in", but as I said, I doubt it is a case of gear whine, as the sound appears to be independent of the actual gears in the transmission.

It doesn't have to coincide with the actual gears; consider this... All the gears in the transmission are in constant mesh. They are all spinning at the same time, and they are all in mesh regardless of the selected gear. 2 pairs of gears carry the load at any given time: the selected pair on the layshaft and output shaft is the first pair, the second is the the input shaft gear (there is only 1 gear on the input shaft), with it's corresponding gear on the layshaft. The latter pair carry the input load regardless of the selected gear. With the exception being in fifth gear, as that connects input and output directly. 1:1 Oh, I forgot to ask, does the noise go away in any gear?

In RED

It's a pity I can't actually listen to it and drive it a half-mile or so... Diagnosing over the internet is hard

[humfrz]

Originally Posted by HachiRo

My only car and I live in a 4-plex with little work room haha.

No excuse ...... just do it the redneck way. Take out the transmission while the car is parked in the front yard, slap it up on the kitchen table, dissemble, wash the parts in the sink ...... lay parts on the kitchen counter and take pictures .......


humfrz

[bcj]

New bearings in the freezer and heat up the transmission body in the stove.

[Ultramaroon]

Originally Posted by bcj

New bearings in the freezer and heat up the transmission body in the stove.

Good stuff. I use dry ice for the cold side.

@Spartarus, the whine I describe follows engine speed both under load and under engine braking. The intensity is about the same no matter which gear. I hear it less in fourth gear and up because of the increase in road noise but it's there all the time.

[Ultramaroon]

Originally Posted by humfrz

No excuse ...... just do it the redneck way. Take out the transmission while the car is parked in the front yard, slap it up on the kitchen table, dissemble, wash the parts in the sink ...... lay parts on the kitchen counter and take pictures .......


humfrz

I like how you think.

Mrs. Ultra drove an auto RS-1 last weekend. I'm thinking we may visit the dealership and ask to test drive a new manual but I already know the result. Up until the holidays my trans made zero noise.

[humfrz]

Originally Posted by bcj

New bearings in the freezer and heat up the transmission body in the stove.

Good idea, but, the freezer is full of elk, venison and catfish bait ......


humfrz

[Stang70Fastback]

That also just happens to coincide with loading and unloading the throwout bearing. How long does this "spin up" take? The input shaft will go from stop to engine RPM in a fraction of the clutch travel. It should be nearly instantaneous. If it takes longer than that, it is not the input shaft you are hearing. That does not necessarily rule out an internal transmission issue, but it rules out the input shaft bearing.

It IS near instantaneous, and yes it occurs during that tiny fraction of pedal travel where the clutch re-engages. The sound also corresponds with the mechanical thunk you can ever so slightly feel when the input shaft is spun up. I promise you it is related to the input shaft spinning up. It might be something else connected to the input shaft, as you mentioned below, but it's definitely related to the input shaft spinning.

Now, you said that the noise goes away clutch-in. You presumably have the clutch in when you are shifting...? So describe this a little better... Does the noise suddenly come back? but only during the shift? Because that points to another problem entirely.

You are right in that I do have the clutch pushed in when I shift. However, this is different than what I mentioned earlier with the transmission being in neutral because the car wasn't moving so pressing the clutch allowed the input shaft to stop spinning.

When I'm changing gears, the input shaft is spinning at high speed with the shifter in 1st gear. I then depress the clutch pedal and shift into 2nd. During that period, the clutch is depressed, but I hear the sound because the input shaft is still spinning. And what I hear is the decrease in speed as it decelerates rapidly as I engage 2nd.

Not necessarily. Adding a thrust load to a worn or failing bearing can silence it, for largely the same reason that pushing on a loose, rattling panel can stop the noise it's making. In fact, most people reporting TOB issues say the noise starts clutch-out after cold start, and only progresses to happening clutch-in when it gets really bad.

That's an excellent point. I suppose it would make sense for the unloaded bearing to make more noise, since there is no load to silence any free play and dampen vibrations.

It doesn't have to coincide with the actual gears; consider this... All the gears in the transmission are in constant mesh. They are all spinning at the same time, and they are all in mesh regardless of the selected gear. 2 pairs of gears carry the load at any given time: the selected pair on the layshaft and output shaft is the first pair, the second is the the input shaft gear (there is only 1 gear on the input shaft), with it's corresponding gear on the layshaft. The latter pair carry the input load regardless of the selected gear. With the exception being in fifth gear, as that connects input and output directly. 1:1 Oh, I forgot to ask, does the noise go away in any gear?

The noise doesn't go away in any gear, to my knowledge. I'll have to pay more attention though, but I know it makes noise in at least 1-4.

Also, what you stated is exactly why I figured it must be input shaft related. Since all the gears in the transmission are always turning together, there is nothing in the transmission that rapidly decelerates when I shift from 1st to 2nd, or 2nd to 3rd, OTHER than the input shaft and its gear, since they have to match engine speed. So the fact that this whine does that seems to rule out everything except the input shaft, as far as I can figure.

[MisterSheep]

Instead of me making a thread about this, i thought id ask u guys.

First off what is the act that has taken place where a company must prove your modifications has caused the specific problem?

Secondly, i have my car at the dealership currently for a weird transmission noise that began. They called me today saying they are haulting any further process and getting a toyota representative out there because of the modifications i had made to the vehicle. I have just an exhaust, stock header, lowering springs, arp studs, and wheels and thats it. I dont see the need to get a representative to look at my mods for a trans noise.

[Teseo]

They are going to void your warranty, prepare a lawyer. You need to be a stupid, well non-car guy
and try to ask how a pipe can ruin the trans or driving with a inch lower can ruin the trans, try not to smile when you done with the questions.

[MisterSheep]

Originally Posted by Teseo

They are going to void your warranty, prepare a lawyer. You need to be a stupid, well non-car guy
and try to ask how a pipe can ruin the trans or driving with a inch lower can ruin the trans, try not to smile when you done with the questions.

And why would they void the warranty? Instead of a "they are going to do it" I have had engine work done by the same dealership in the past and they didnt even question the mods.

[chaoskaze]

Originally Posted by go_a_way1

Fuk my new hair style, here I come!




awwww