weird scratching noise when engine breaking with second gear

[Donut]

Hello,

just had a moment of shock when I used my usual engine braking routine. I wanted to loose some speed and shifted into the second gear when I heard a high pitched scratching noise, as if to metal plates would scrape each other (not the usual sound when shifting). I then tried to reproduce the issue and it occurred a couple of more times but it is gone now. I am worried, since I need my car in great shape for the coming road trip.

Do you have any idea what might be wrong?

thx for your thoughts.

[3dplane]

Can you give more details? What was the speed? What gear did you go to second gear from? Do you rev match? (neutral,clutch pedal released,blip throttle,clutch pedal depressed,put shifter in gear)

Did the noise occur as you are pulling the shifter into 2nd gear (and the synchronizer is working at this time) or after it is already in gear and you are in the process of releasing the clutch pedal? Or clutch already released?

If you give details I could try it with mine.

[Donut]

thx for your help.

I wanted to shift from 3rd into second to prepare for a stop sign ahead. The speed was maybe around 15-20mph. Unfortunately, I am not so fast with my hand and leg coordination do to the described shifting routine. Instead, I just depress the clutch, let a new gear glide in, and then let the clutch gently come back up.

The noise occurred when the clutch started to engage the engine and disappeared when I depressed the clutch again to switch back to the 3rd gear.

[inuvik]

I can only think of 2 things it might be. Either the throw out bearing or the pressure plate on the clutch.

[ThunderG]

I have a 2015 DE 5speed. Sometimes I hear a little screech when starting the engine. It only
lasts a fraction of a second and sounds like a belt. The belt is very tight and the car only has
4500 miles on it. It doesn't happen often, maybe only once every week or two. Since I have
to hold the clutch in to start the car maybe that has something to do with it.

[3dplane]

thx for your help.

I wanted to shift from 3rd into second to prepare for a stop sign ahead. The speed was maybe around 15-20mph. Unfortunately, I am not so fast with my hand and leg coordination do to the described shifting routine. Instead, I just depress the clutch, let a new gear glide in, and then let the clutch gently come back up.

The noise occurred when the clutch started to engage the engine and disappeared when I depressed the clutch again to switch back to the 3rd gear.

Hmm interesting. I can only rule out a synchronizer from that. The throwout bearing works under pressure when the clutch pedal is depressed,but has a chance to be loose (play) with the pedal released so that can go both ways. And does not care what gear the transmission is in.

I would say don't worry about it for your trip unless it becomes consistent. And if it does become consistent,then it will be easier to duplicate and diagnose.

[3dplane]

I have a 2015 DE 5speed. Sometimes I hear a little screech when starting the engine. It only
lasts a fraction of a second and sounds like a belt. The belt is very tight and the car only has
4500 miles on it. It doesn't happen often, maybe only once every week or two. Since I have
to hold the clutch in to start the car maybe that has something to do with it.

Mine does the same little screech on startup once in a while. Some anomaly with the belt. I don't worry about it.

[deleted user]

My brother had a screeching sound that we determined was the throwout bearing at 70k miles in his Tacoma. 110k now and it has not done it in over 20 k miles. Maybe it got dry and the heat from making the noise melted some of the grease and allowed it to get where it is needed. I have no other rational explanation and he is superb at getting max miles out of a clutch. he learned when the used truck he bought dropped the center thrust bearing down into the oil pan and the crank was moving 1/4 inch front to rear when you used the clutch, watching the front pully on a much older, much more abused carbed 22r motor.

regards
mech