Go Back   LS1TECH > CHASSIS, SUSPENSION, APPEARANCE > Manual Transmission
Sign in using an external account
Register Forgot Password?
Search

Manual Transmission
T56 | T5 | MN12 | Clutches | Hydraulics | Shifters
Sponsored by
McLeod Clutch

Reply
 
Thread Tools Search this Thread
Old 01-19-2010, 07:00 PM   #1
Banned
Garage is empty, add now
 
Trader Rating: 40
Join Date: Dec 2006
Location: Austin, Tx
Posts: 1,018
Send a message via AIM to westtexasbuff Send a message via Yahoo to westtexasbuff
Exclamation Grinding When Downshifting Only, Syncros???

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?
westtexasbuff is offline   Reply With Quote
Old 01-20-2010, 01:12 PM   #2
Banned
Garage is empty, add now
 
Trader Rating: 40
Join Date: Dec 2006
Location: Austin, Tx
Posts: 1,018
Send a message via AIM to westtexasbuff Send a message via Yahoo to westtexasbuff
Default

Bump, anybody?
westtexasbuff is offline   Reply With Quote
Old 01-20-2010, 04:58 PM   #3
Rockerator
Garage is empty, add now
 
PewterScreaminMach's Avatar
 
Trader Rating: 7
Join Date: Sep 2006
Location: Austin, TX
Posts: 2,634
Default

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.
PewterScreaminMach is offline   Reply With Quote
Old 01-20-2010, 06:25 PM   #4
TECH Junkie
Garage is empty, add now
 
ae13291's Avatar
 
Trader Rating: 8
Join Date: Jun 2007
Location: san fernando valley, california
Posts: 3,059
Send a message via AIM to ae13291
Default

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?
__________________
'99 Camaro Z28 M6 SOLD!
ae13291 is offline   Reply With Quote
Old 01-21-2010, 12:03 PM   #5
Save the manuals!
Garage is empty, add now
 
wssix99's Avatar
 
Trader Rating: 5
Join Date: Dec 2007
Location: Chicago, IL
Posts: 7,229
Default

Quote:
Originally Posted by PewterScreaminMach View Post
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.
+1 - I had the exact same experience between 1 & 2.
wssix99 is online now   Reply With Quote
Old 01-21-2010, 05:45 PM   #6
Banned
Garage is empty, add now
 
Trader Rating: 40
Join Date: Dec 2006
Location: Austin, Tx
Posts: 1,018
Send a message via AIM to westtexasbuff Send a message via Yahoo to westtexasbuff
Default

Quote:
Originally Posted by ae13291 View Post
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?
It was an LS2 style aluminum flywheel. Feels a lot better than stock, and was much lighter. Shifts a lot better though. Haven't really gotten the chance to get on it much because I fix one thing, and another breaks...
westtexasbuff is offline   Reply With Quote
Old 01-21-2010, 05:45 PM
LS1Tech
Pontiac Firebird




Paid Advertisement
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
4th gear grind only when going into gear HELP moe24 Manual Transmission 9 02-26-2014 11:15 AM
rebuilt t56 and wont downshift 3-2 Centerfold_Firehawk Manual Transmission 13 08-15-2012 05:28 PM
fresh trans rebuild, downshift grinding 2nd intermittently. RADEoN Manual Transmission 28 03-07-2011 08:59 PM
Downshift problem.. shaking.. RollinSScamaro Automatic Transmission 6 11-25-2006 06:20 PM
2nd gear grinds after missed shift. '04 C5 1700 miles. emess Corvette Performance 4 11-30-2004 11:01 AM


Tags
camaro, downshift, downshifting, fast, gear, grind, grinds, lot, makes, manual, noise, rear, syncros, t5, trans, transmission


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off



Join Ls1Tech

All times are GMT -5. The time now is 01:29 PM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Service - Privacy Statement - JOBS
Emails & Contact Details