4+3 manuel 88 Corvette question
Thread Starter
Intermediate
Joined: Dec 2016
Posts: 48
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From: Pinehurst North Carolina
4+3 manuel 88 Corvette question
Sometimes when trying to go in reverse , the gears will grind so if I then go to first gear and then reverse it works fine. Any thoughts ? Thanks
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
Normal. Or not. Depends.
It's normal for the gears to grind going into reverse after a clutch depress, because even though you pressed the clutch pedal, the clutch disk has inertia, like a small flywheel, and keeps on spinning for a bit -especially when the trans oil is warm, thin and the gears can spin easily. Sometimes, the friction of the pilot bearing, windage of the flywheel and pressure plate are enough to keep the clutch disk and input shaft spinning...so when you move to reverse (which is unsychronized) you get a grind. Putting it in first, first, uses the first gear synchronizer to stop the input shaft from rotating...then you move to reverse and everything is stopped, so you get a "grind-free" engagement into reverse.
Now...of the grinding into reverse goes on and on...or if you get it into first, then dally in neutral for a few seconds and it still grinds into reverse, then that is a good sign that you're clutch isn't fully releasing. You'd need to address your hydraulic release system.
So if the grinding is momentary, or only on "clutch in", that is normal for that 4+3. If it is persistent and want to continue after stopping the input shaft with the first gear synchro...that is not normal.
It's normal for the gears to grind going into reverse after a clutch depress, because even though you pressed the clutch pedal, the clutch disk has inertia, like a small flywheel, and keeps on spinning for a bit -especially when the trans oil is warm, thin and the gears can spin easily. Sometimes, the friction of the pilot bearing, windage of the flywheel and pressure plate are enough to keep the clutch disk and input shaft spinning...so when you move to reverse (which is unsychronized) you get a grind. Putting it in first, first, uses the first gear synchronizer to stop the input shaft from rotating...then you move to reverse and everything is stopped, so you get a "grind-free" engagement into reverse.
Now...of the grinding into reverse goes on and on...or if you get it into first, then dally in neutral for a few seconds and it still grinds into reverse, then that is a good sign that you're clutch isn't fully releasing. You'd need to address your hydraulic release system.
So if the grinding is momentary, or only on "clutch in", that is normal for that 4+3. If it is persistent and want to continue after stopping the input shaft with the first gear synchro...that is not normal.
