Gear Grinding sound on Downshift into 2nd

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angusis2fast4u
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Gear Grinding sound on Downshift into 2nd

Postby angusis2fast4u » Fri Sep 06, 2013 7:47 pm

This has started happening pretty suddenly just now but whenever i go to downshift into 2nd from 3rd it makes a sound like two gears grinding . This scares me because i had a new Exedy sports tuff clutch installed about 1,500km's ago.

I had a look around some people are saying put new oil in and others are saying it could be a synchro since it's only on the 1 gear. I don't want to take it back to this mechanic if its not needed because well at the moment this is annoying me because it's a brand new clutch.

What is happening to my gearbox and how do i fix it!?

*EDIT - clutch installed at 153K kms and is on about 154.8k now
~Angus
2001 Silver NB8B
Past: Grey 1990 Eunos Roadster

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Re: Gear Grinding sound on Downshift into 2nd

Postby NitroDann » Fri Sep 06, 2013 8:13 pm

Start by making sure the clutch hydraulics are working correctly.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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angusis2fast4u
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Re: Gear Grinding sound on Downshift into 2nd

Postby angusis2fast4u » Fri Sep 06, 2013 8:52 pm

NitroDann wrote:Start by making sure the clutch hydraulics are working correctly.

Dann


DIY or best take it to mechanic?
~Angus
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Past: Grey 1990 Eunos Roadster

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Re: Gear Grinding sound on Downshift into 2nd

Postby DaveWA » Fri Sep 06, 2013 9:28 pm


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hks_kansei
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Re: Gear Grinding sound on Downshift into 2nd

Postby hks_kansei » Fri Sep 06, 2013 9:41 pm

Does it do it if you double clutch?

If not, probably synchro.

Especially since 2nd gear usually cops the worst from people thinking "I are teh racecar drivar, I ken shift geers in .25 seconds!"
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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angusis2fast4u
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Re: Gear Grinding sound on Downshift into 2nd

Postby angusis2fast4u » Fri Sep 06, 2013 11:39 pm

hks_kansei wrote:Does it do it if you double clutch?

If not, probably synchro.

Especially since 2nd gear usually cops the worst from people thinking "I are teh racecar drivar, I ken shift geers in .25 seconds!"


:roll:
~Angus
2001 Silver NB8B
Past: Grey 1990 Eunos Roadster

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Re: Gear Grinding sound on Downshift into 2nd

Postby deviant » Fri Sep 06, 2013 11:53 pm

angusis2fast4u wrote:
hks_kansei wrote:Does it do it if you double clutch?

If not, probably synchro.

Especially since 2nd gear usually cops the worst from people thinking "I are teh racecar drivar, I ken shift geers in .25 seconds!"


:roll:


Not sure why you are rolly eyes....He speaks the truth.

Check the clutch hydraulics are working.

Change the gearbox oil. Many threads exist on this.

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angusis2fast4u
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Re: Gear Grinding sound on Downshift into 2nd

Postby angusis2fast4u » Sat Sep 07, 2013 12:00 am

deviant wrote:
angusis2fast4u wrote:
hks_kansei wrote:Does it do it if you double clutch?

If not, probably synchro.

Especially since 2nd gear usually cops the worst from people thinking "I are teh racecar drivar, I ken shift geers in .25 seconds!"


:roll:


Not sure why you are rolly eyes....He speaks the truth.

Check the clutch hydraulics are working.

Change the gearbox oil. Many threads exist on this.


It was the only smiley that says "im guilty of that"

Yeah im going to check trans oil and and search how to check hydralics, clutch feels fine and im guessing its just the synchros since all of that was just apart for the new clutch
~Angus
2001 Silver NB8B
Past: Grey 1990 Eunos Roadster

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hks_kansei
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Re: Gear Grinding sound on Downshift into 2nd

Postby hks_kansei » Sat Sep 07, 2013 12:07 am

Synchromesh allows downchanges (and upchanges) when the engine speed and the road speed do not match.
It basically helps the gears to mesh correctly rather than grinding each other until they mesh.


Double clutching is where you downchange and rev match to remove the need for the synchro to do anything.

Therefore, if the 3-2 shift crunches normally, but doesn't when doible clutched, it's possibly a synchro.
If it crunches no matter what, it's probably something else.


Check the easiest things first, master cylinder, slave, fluid, bleed.
Then check the gearbox has the correct amount of oil in it (or change it if it's due)
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Re: Gear Grinding sound on Downshift into 2nd

Postby NitroDann » Sat Sep 07, 2013 12:08 am

All of that wasnt just apart to change the clutch.

Check the hydraulics.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: Gear Grinding sound on Downshift into 2nd

Postby hks_kansei » Sat Sep 07, 2013 12:12 am

NitroDann wrote:All of that wasnt just apart to change the clutch.


Not suggesting it was, but depending on the car's previous owners etc it's possibly had 150,000km of people sledgehammer shifting into second every day.



Maybe I'm just getting pedantic about hard shifting since I've been driving a column shifted manual the past few days.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Re: Gear Grinding sound on Downshift into 2nd

Postby NitroDann » Sat Sep 07, 2013 12:19 am

I was replying to angus, you ninja'd me.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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hks_kansei
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Re: Gear Grinding sound on Downshift into 2nd

Postby hks_kansei » Sat Sep 07, 2013 12:23 am

Ah, fair enough then.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)


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