Transmission Grinding
02-27-2011, 07:49 AM
#41
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It's definitely grinding! It's not the starter nor chatter. I had a bit of chatter before changing the clutch.
Another note i may add is... If i shift very slow, no matter how high the RPMS are, it wont grind. So another words, it only grinds when shifting normal/fast, or when i rev up the engine and shift fast.
Also, the clutch does feel spongy.
Another note i may add is... If i shift very slow, no matter how high the RPMS are, it wont grind. So another words, it only grinds when shifting normal/fast, or when i rev up the engine and shift fast.
Also, the clutch does feel spongy.
02-27-2011, 08:54 AM
#42
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zerostyle, please explain how the transmission mount can be the cause.
Since the transmission is solidly bolted to the engine, the whole assembly moves together. The shifter and slave cylinder are bolted to the transmission, so they move with the assembly, too. I just don't see a way for the transmission mount to change the way those things work/don't work properly.
tyau, good call!! A damaged pilot bearing is a good possibility I hadn't thought of before. It could transmit enough torque to the transmission input shaft to cause problems with shifting even with the clutch fully disengaged. That would be hard on the synchronizers. It could also be making a grinding noise when the pedal was depressed with the transmission in neutral.
Since the transmission is solidly bolted to the engine, the whole assembly moves together. The shifter and slave cylinder are bolted to the transmission, so they move with the assembly, too. I just don't see a way for the transmission mount to change the way those things work/don't work properly.
tyau, good call!! A damaged pilot bearing is a good possibility I hadn't thought of before. It could transmit enough torque to the transmission input shaft to cause problems with shifting even with the clutch fully disengaged. That would be hard on the synchronizers. It could also be making a grinding noise when the pedal was depressed with the transmission in neutral.
Is the pilot bearing the same as the throwout bearing? If so, i replaced that when i replaced my clutch. It's not to say that a brand new one may have gone bad, but i highly doubt it.
02-27-2011, 09:15 AM
#44
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No. The pilot bearing supports the front end of the transmission input shaft in the rear end of the crankshaft. The throwout bearing is between the clutch fork (or CSC in later cars) and the fingers on the diaphragm spring in the clutch pressure plate.
The pilot bearing is much smaller than the throwout bearing, and it could be damaged if the transmission is allowed to drop down in the first inch or so as it's being removed from the engine.
The pilot bearing is much smaller than the throwout bearing, and it could be damaged if the transmission is allowed to drop down in the first inch or so as it's being removed from the engine.
02-27-2011, 09:23 AM
#45
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No. The pilot bearing supports the front end of the transmission input shaft in the rear end of the crankshaft. The throwout bearing is between the clutch fork (or CSC in later cars) and the fingers on the diaphragm spring in the clutch pressure plate.
The pilot bearing is much smaller than the throwout bearing, and it could be damaged if the transmission is allowed to drop down in the first inch or so as it's being removed from the engine.
The pilot bearing is much smaller than the throwout bearing, and it could be damaged if the transmission is allowed to drop down in the first inch or so as it's being removed from the engine.
Wait, Now that i think of it... We did remove the tranny by itself after we had installed both to make sure we didnt forget a bolt on the flywheel...
Would the pilot bearing be hard to replace?
02-27-2011, 11:14 AM
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pilot bearing sounds like a possibility. but would that cause all the symptoms...grinding sensation every gear, only on up and not downshifts...no grinding when holding the cltuch letting rpms drop under 3k then shifting. and from his description of the pilot bearing it doesnt sound like itll be easy
02-27-2011, 01:39 PM
#47
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The hard part of replacing the pilot bearing is getting to it. You'll need to remove the transmission from the car, and the clutch from the flywheel.
I think it explains all the symptoms. I'm pretty sure the load on the synchronizers is less when shifting down, because the parts in the transmission are going closer to the same speed. Also, a downshift uses a different side of the synchronizer teeth than the upsift.
I think it explains all the symptoms. I'm pretty sure the load on the synchronizers is less when shifting down, because the parts in the transmission are going closer to the same speed. Also, a downshift uses a different side of the synchronizer teeth than the upsift.
02-27-2011, 02:50 PM
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eztax...does your gear placement feel any different? mine does...when going to 5th i dont have to go as "upper right" and 6th i dont have to go as "lower right". it also doesnt look the same....
02-27-2011, 02:57 PM
#49
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Hmmm... mine doesnt feel like that... or at least i dont notice it....
In the beginning, I had to re adjust the guide on the shift lever because it wasnt letting the gears go all the way in.
In the beginning, I had to re adjust the guide on the shift lever because it wasnt letting the gears go all the way in.
03-14-2011, 07:28 PM
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Did you anything??? Yeah my pedal got stuck the other day...and occasionally my tranny will grind and wont stop till i let go of the clutch. Its weird and embarassing. It happened to me at a meet and it prolly looked like im a rookie and cant drive
03-18-2011, 08:52 AM
#55
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http://www.ls1tech.com/forums/manual...going-out.html
Read this, Its written by LS1 guys but maybe it will help you guys.
Read this, Its written by LS1 guys but maybe it will help you guys.
03-18-2011, 09:07 AM
#56
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Maybe i missed it in the thread, but have you re-aligned your shifting plate since the tranny was re-installed?
Mine was off by an 1/8th an inch and caused 5/6th to grind...
Mine was off by an 1/8th an inch and caused 5/6th to grind...
03-18-2011, 09:42 AM
#57
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The pilot bearing is a small ring that the input shaft of the tranny slides into.. Its used as a guide for that end. Its made from brass which is an inherently soft material. If it gets bent scored or damaged in any way this could lead to play in the input shaft resulting in a vibration or"grinding"feel.. Most of the grinding I've ever heard of comes from air in the clutch line or a bad syncros....
Good news is the brass pilot bearing is like $3
Bad news is the tranny n clutch assembly has to come out..
Good luck hope u get it fixed!
Ray
Good news is the brass pilot bearing is like $3
Bad news is the tranny n clutch assembly has to come out..
Good luck hope u get it fixed!
Ray
02-09-2012, 07:42 PM
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I have the same issue =( I adjusted my shifter plate but no luck, I will try to bleed the clutch and adjust the clutch pedal and see what happens. I have 5k miles on my new cd009 trans, new clutch n flywheel, throwout bears etc everything has 5k miles on it.