Grinding When Downshifting Only, Syncros???
#1
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So I just installed a new LS7 clutch and aluminum flywheel. Drove fine. Drove it for about 40 miles, and my rear blew. Put in new gears, and posi. Went for a spin, and now there's a ton of rattling going on in my transmission when I have the car in neutral, when I press on the clutch, the rattling goes away.
Now, I drive, shifts normal going up in gears, but when I want to downshift from 3rd to 2nd, it grinds and I can't shift into 2nd. Also grinds downshifting from 5th to 4th. Doesn't grind when downshifting from 3rd to 1st.
Doesn't grind when downshifting 6th to 5th, or 4th to 3rd.
I've heard that syncros in these cars go bad when dropping the tranny.
Any ideas? Is it the syncros?
Now, I drive, shifts normal going up in gears, but when I want to downshift from 3rd to 2nd, it grinds and I can't shift into 2nd. Also grinds downshifting from 5th to 4th. Doesn't grind when downshifting from 3rd to 1st.
Doesn't grind when downshifting 6th to 5th, or 4th to 3rd.
I've heard that syncros in these cars go bad when dropping the tranny.
Any ideas? Is it the syncros?
#3
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I had an issue with that but it was only downshifting to third. Thought it might be the friction cones worn down but when we pulled it apart they were fine. Turned out to be the synchro and gear teeth being worn down. Replaced third gear and the 3/4 synchro and no more issues.
If it's only doing it on downshifts and only on certain gears, it's an internal transmission issue, though. It will require a tear down. Good luck, man.
If it's only doing it on downshifts and only on certain gears, it's an internal transmission issue, though. It will require a tear down. Good luck, man.
#4
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after you go to a aluminum flywheel you should experiance more noise, like a deisal lol.
how do you like the aluminum LS7 combo is it much differant? any loss of torque? and which aluminum flywheel?
how do you like the aluminum LS7 combo is it much differant? any loss of torque? and which aluminum flywheel?
#5
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I had an issue with that but it was only downshifting to third. Thought it might be the friction cones worn down but when we pulled it apart they were fine. Turned out to be the synchro and gear teeth being worn down. Replaced third gear and the 3/4 synchro and no more issues.
If it's only doing it on downshifts and only on certain gears, it's an internal transmission issue, though. It will require a tear down. Good luck, man.
If it's only doing it on downshifts and only on certain gears, it's an internal transmission issue, though. It will require a tear down. Good luck, man.