Overly hard shifts c6 m6
Thread Starter
Safety Car
Joined: Jun 2011
Posts: 4,352
Likes: 32
From: Canton Michigan
Overly hard shifts c6 m6
Just recently did a motor swap so clutch had to come off and go back on..
It is a Mcleod RXT steel flywheel, and a mgw short shifter as well i believe it is..
Ever since everything has been reinstalled the shifting between gears is a hell of a lot harder then it use to be.. there is no way you could fast shift. If i push in the clutch and try to go from say 2nd to 3rd.. its hard and a 1sec delay before it will let me do it.. fluid is fresh all new... I mean you have to force it into gear to make it go in. Does not grind gears when u force it.
1st gear engage is also pretty rough might be common with that type of clutch idk never had a twin disk.. but if you dont give it enough gas the car will shake like the paint shake at a home depot mixing up paint.
Also getting into Reverse is a ***** Effer. We did how ever adjust the shifter. Help a lil but not allot.
also not sure if the engine upgrades could cause this as well. Or clutch bolts til tight
Looking for ideas, suggestions and all the above.. thank you.
It is a Mcleod RXT steel flywheel, and a mgw short shifter as well i believe it is..
Ever since everything has been reinstalled the shifting between gears is a hell of a lot harder then it use to be.. there is no way you could fast shift. If i push in the clutch and try to go from say 2nd to 3rd.. its hard and a 1sec delay before it will let me do it.. fluid is fresh all new... I mean you have to force it into gear to make it go in. Does not grind gears when u force it.
1st gear engage is also pretty rough might be common with that type of clutch idk never had a twin disk.. but if you dont give it enough gas the car will shake like the paint shake at a home depot mixing up paint.
Also getting into Reverse is a ***** Effer. We did how ever adjust the shifter. Help a lil but not allot.
also not sure if the engine upgrades could cause this as well. Or clutch bolts til tight
Looking for ideas, suggestions and all the above.. thank you.
Last edited by UmX; Jul 11, 2015 at 08:38 PM.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Sounds to me like your slave is not disengaging your clutch all the way.
Did you double check stack height and shim the slave if necessary?
If you jack up the rear wheels (safely block car from moving) and you push in the clutch with the car in gear, do the wheels stop? Is it easier to shift with the back wheels up in the air?
These would be symptoms of a clutch that is not disengaging.
You might get lucky and bleed it a lot and make it better....
Did you double check stack height and shim the slave if necessary?
If you jack up the rear wheels (safely block car from moving) and you push in the clutch with the car in gear, do the wheels stop? Is it easier to shift with the back wheels up in the air?
These would be symptoms of a clutch that is not disengaging.
You might get lucky and bleed it a lot and make it better....
Thread Starter
Safety Car
Joined: Jun 2011
Posts: 4,352
Likes: 32
From: Canton Michigan
I will try this tomorrow. I don't believe the clutch was shimmed on original install. Can't answer that question.
Sounds to me like your slave is not disengaging your clutch all the way.
Did you double check stack height and shim the slave if necessary?
If you jack up the rear wheels (safely block car from moving) and you push in the clutch with the car in gear, do the wheels stop? Is it easier to shift with the back wheels up in the air?
These would be symptoms of a clutch that is not disengaging.
You might get lucky and bleed it a lot and make it better....
Did you double check stack height and shim the slave if necessary?
If you jack up the rear wheels (safely block car from moving) and you push in the clutch with the car in gear, do the wheels stop? Is it easier to shift with the back wheels up in the air?
These would be symptoms of a clutch that is not disengaging.
You might get lucky and bleed it a lot and make it better....
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Thread Starter
Safety Car
Joined: Jun 2011
Posts: 4,352
Likes: 32
From: Canton Michigan
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Maybe you can borrow a stock shifter. The alignment of the shifter is done with the two shifter box bolts.
You can get the procedure from here if you need it. I'm afraid that my first guess may be the right one however. I hope I'm wrong as that's a big job to fix up. You have to remove everything to shim the slave.
Your instructions for your clutch should discuss this, did they?
You can get the procedure from here if you need it. I'm afraid that my first guess may be the right one however. I hope I'm wrong as that's a big job to fix up. You have to remove everything to shim the slave.
Your instructions for your clutch should discuss this, did they?
Thread Starter
Safety Car
Joined: Jun 2011
Posts: 4,352
Likes: 32
From: Canton Michigan
Well clutch was installed last summer by someone else. And worked ok I guess. But now it's all goofy when I pulled out the motor..
Maybe you can borrow a stock shifter. The alignment of the shifter is done with the two shifter box bolts.
You can get the procedure from here if you need it. I'm afraid that my first guess may be the right one however. I hope I'm wrong as that's a big job to fix up. You have to remove everything to shim the slave.
Your instructions for your clutch should discuss this, did they?
You can get the procedure from here if you need it. I'm afraid that my first guess may be the right one however. I hope I'm wrong as that's a big job to fix up. You have to remove everything to shim the slave.
Your instructions for your clutch should discuss this, did they?
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Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Sounds like an install problem of some sort. Did you pull the torque tube when you pulled the engine or did you pull the engine out from the front? That might eliminate the shifter if you left the tube in place.
Did you use the same flywheel or a new flywheel? Perhaps they have a different thickness....
Did you use the same flywheel or a new flywheel? Perhaps they have a different thickness....
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
You mention the clutch chatters a lot when engaging. Is that something new too?
Perhaps you didn't put the clutch back together properly or perhaps forgot to loctite the bolts? It's starting to sound like a clutch assembly issue. Again I hope I'm wrong.
Perhaps you didn't put the clutch back together properly or perhaps forgot to loctite the bolts? It's starting to sound like a clutch assembly issue. Again I hope I'm wrong.
Thread Starter
Safety Car
Joined: Jun 2011
Posts: 4,352
Likes: 32
From: Canton Michigan
Well I followed the install guide for the torque specs. I doubt the bolts would of backed out yet. Less then 100 miles on the car since back together. It did chatter before I took this all apart ad well
Thread Starter
Safety Car
Joined: Jun 2011
Posts: 4,352
Likes: 32
From: Canton Michigan
Lockout is back on the transmission on the top.
C5 instructions, but it's the same, except for the console removal.
Corvette shifter adjustment video by froggy - YouTube
C5 instructions, but it's the same, except for the console removal.
Corvette shifter adjustment video by froggy - YouTube
Still when ur trying to go to another gear car makes u wait a half second before it will engage into the next gear,.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Engine off, car stationary, no clutch
Engine off, car stationary, clutch in
Engine on, car stationary, clutch in
Engine on, car coasting, clutch in
I'm still thinking it's clutch related, the fact it disengages on jack stands says it's not, but it would make sense it's clutch related since difficulty shifting in every gear IMHO means the clutch isn't disengaging all the way or the shifter or shifter rod is misaligned. The tests above will eliminate the clutch.
We need to think methodically.
It shifted fine before, now it doesn't. What changed? You swapped the engine. Now it is very hard to shift like the syncros are working over time, and it makes a lot more judder/noise when you take off like the clutch floater is loose.
Did I get it right? Anything to add?
Any chance you bent the shift rod back to the transmission? The fact it's impossible to get into reverse lead me to this question.
I hope someone smarter than me can chime in with some thoughts...
Thread Starter
Safety Car
Joined: Jun 2011
Posts: 4,352
Likes: 32
From: Canton Michigan
Engine off, car stationary, no clutch Normal
Engine off, car stationary, clutch in Normal
Engine on, car stationary, clutch in Normal
Engine on, car coasting, clutch in Front end on stands cant test
Im going have to get it back on a lift and check under neath only way..
As i get close to 4k rpms as well. the car starts to vibrate heavily which feels like it is coming from the drive train
I revved it in N to 4k for about 5 secs.. no vibrations as it came down to idle had a lil bit. but thnking that might be the larger cam or stroked crankshaft at that point,
Engine off, car stationary, clutch in Normal
Engine on, car stationary, clutch in Normal
Engine on, car coasting, clutch in Front end on stands cant test
Im going have to get it back on a lift and check under neath only way..
As i get close to 4k rpms as well. the car starts to vibrate heavily which feels like it is coming from the drive train
I revved it in N to 4k for about 5 secs.. no vibrations as it came down to idle had a lil bit. but thnking that might be the larger cam or stroked crankshaft at that point,
Does it do the same thing:
Engine off, car stationary, no clutch
Engine off, car stationary, clutch in
Engine on, car stationary, clutch in
Engine on, car coasting, clutch in
I'm still thinking it's clutch related, the fact it disengages on jack stands says it's not, but it would make sense it's clutch related since difficulty shifting in every gear IMHO means the clutch isn't disengaging all the way or the shifter or shifter rod is misaligned. The tests above will eliminate the clutch.
We need to think methodically.
It shifted fine before, now it doesn't. What changed? You swapped the engine. Now it is very hard to shift like the syncros are working over time, and it makes a lot more judder/noise when you take off like the clutch floater is loose.
Did I get it right? Anything to add?
Any chance you bent the shift rod back to the transmission? The fact it's impossible to get into reverse lead me to this question.
I hope someone smarter than me can chime in with some thoughts...
Engine off, car stationary, no clutch
Engine off, car stationary, clutch in
Engine on, car stationary, clutch in
Engine on, car coasting, clutch in
I'm still thinking it's clutch related, the fact it disengages on jack stands says it's not, but it would make sense it's clutch related since difficulty shifting in every gear IMHO means the clutch isn't disengaging all the way or the shifter or shifter rod is misaligned. The tests above will eliminate the clutch.
We need to think methodically.
It shifted fine before, now it doesn't. What changed? You swapped the engine. Now it is very hard to shift like the syncros are working over time, and it makes a lot more judder/noise when you take off like the clutch floater is loose.
Did I get it right? Anything to add?
Any chance you bent the shift rod back to the transmission? The fact it's impossible to get into reverse lead me to this question.
I hope someone smarter than me can chime in with some thoughts...
Last edited by UmX; Jul 14, 2015 at 10:48 AM.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Is it a different flywheel? Any chance you forgot to put in the pilot bearing? Any change in motor mounts?
I'm kind of grasping at straws here I hope someone smarter chimes in...
I'm kind of grasping at straws here I hope someone smarter chimes in...