What is grinding?

Synchros shot? Weird noises while shifting? Not sure what needs to be replaced?
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masfenix
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What is grinding?

Post by masfenix »

How do I tell if my gears are grinding? My 1st - 2nd shifts are always jerky so is it because i just need practice or something wrong with the syncro/gear?

If my gears were grinding, what sort of noise would I be hearing? Would I have trouble shifting into second? would it be super jerky?
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AHTOXA
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Re: What is grinding?

Post by AHTOXA »

Grinding is just that - grinding. You would know when you hear it. It's loud and almost physically painful to hear, mainly because every manual driver hates nothing more than grinding.
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Re: What is grinding?

Post by Rope-Pusher »

masfenix wrote:How do I tell if my gears are grinding? My 1st - 2nd shifts are always jerky so is it because i just need practice or something wrong with the syncro/gear?

If my gears were grinding, what sort of noise would I be hearing? Would I have trouble shifting into second? would it be super jerky?
Technically, your gears (except maybe Reverse) are in constant mesh and don't "grind". Now, if your synchronizers are not working, the blocking rings aren't bringing the gear to the proper speed and when the synchronizer sleeve hits the speed gear with their speeds not synchronized, it hits the clutching teeth and they hop and skip across the tops of them and round off the tips. when this occurs, this is the noise that people refer to as "Grinding the gears" but is formally known as synchronizer "Clash".

First, determine if you clutch is fully releasing. Clutch engagement point should be 25-40 mm "up" from fully depressed position. If not, and the clutch is only partially disengaged and dragging during the shift, the even "good" synchronizers can't handle it and clash. Another way to evaluate this is if you cannot shift from Neutral into 1st gear smoothly unless the engine is shut off your clutch is dragging.

If the clutch isn't dragging, but there is still clash, then the synchronizer is worn and needs to be replaced - OR - you need to change your driving style to not stress the synchronizer. Try shifting more slowly and if that doesn't help, try double-clutching your shifts. A lot of guys will do a backflip into the seat of their car if it keeps them from having to get their transmission replaced/repaired. That option is certainly open to you, but be careful not to miss the seat and land on the shifter.
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comingbackdown
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Re: What is grinding?

Post by comingbackdown »

Evidently my 1st gear has no synchro, since I managed to grind it. It was a grind, too, not just that whizzing bullet sound of a synchro getting raped. Sounded like a slower version of a gatling gun. Ick!
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fa22raptorf22
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Re: What is grinding?

Post by fa22raptorf22 »

I tend to slightly grind reverse every so often.

Its just that I am too lazy to let the car to to a complete stop. What can you do lol :roll:
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Re: What is grinding?

Post by potownrob »

fa22raptorf22 wrote:I tend to slightly grind reverse every so often.

Its just that I am too lazy to let the car to to a complete stop. What can you do lol :roll:
shift to another gear then back to reverse - it is advised to not shift to 2nd then reverse since 2nd gets enough abuse as it is
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Re: What is grinding?

Post by Rope-Pusher »

comingbackdown wrote:Evidently my 1st gear has no synchro, since I managed to grind it. It was a grind, too, not just that whizzing bullet sound of a synchro getting raped. Sounded like a slower version of a gatling gun. Ick!
Old rwd 3-speeds may have been the last Amish transmissions w/o a synchro on 1st gear. Your first gear is in constant mesh and NOT grinding. You have a dysfunctional synchronizer on 1st gear that is clashing.
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Re: What is grinding?

Post by comingbackdown »

Rope-Pusher wrote:
comingbackdown wrote:Evidently my 1st gear has no synchro, since I managed to grind it. It was a grind, too, not just that whizzing bullet sound of a synchro getting raped. Sounded like a slower version of a gatling gun. Ick!
Old rwd 3-speeds may have been the last Amish transmissions w/o a synchro on 1st gear. Your first gear is in constant mesh and NOT grinding. You have a dysfunctional synchronizer on 1st gear that is clashing.
It would've helped if the truck wasn't moving...
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Re: What is grinding?

Post by Rope-Pusher »

comingbackdown wrote:
Rope-Pusher wrote:
comingbackdown wrote:Evidently my 1st gear has no synchro, since I managed to grind it. It was a grind, too, not just that whizzing bullet sound of a synchro getting raped. Sounded like a slower version of a gatling gun. Ick!
Old rwd 3-speeds may have been the last Amish transmissions w/o a synchro on 1st gear. Your first gear is in constant mesh and NOT grinding. You have a dysfunctional synchronizer on 1st gear that is clashing.
It would've helped if the truck wasn't moving...
That's how they got away with unsynchronized 1st gear. It was assumed the driver would come to a stop before shifting into 1st. 2nd was good enough for any time the vehicle still had forward motion.
'08 Jeep Liberty 6-Speed MT - "Last of the Mohicans"
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