LS7 Clutch Install/Torque Tube Questions (Specific Questions Inside)
07-07-2016, 02:23 AM
#1
Instructor
Thread Starter
LS7 Clutch Install/Torque Tube Questions (Specific Questions Inside)
Good Evening Folks,
I hope all is well!
I have a few questions about the LS7 Clutch Install on my 2001 C5 Z06.
Brief rundown/background:
I was running the Z at the local track (the car is stock other than Vararam VR-B2, Borla Stingers and C6Z Shifter). I did a small burn out in the water box to heat/scuff the tires a bit. I launched the car, it drove great, went through all the gears fine, ran 12.9 @ 113 (4200' DA) and got me back to the pits with no problem. When I left the track I had heard a whine/hissing noise coming from the shifter area. It was most prominent (so I thought) when I was driving and in gear. After changing diff fluid and trans fluid (AmsOil Torque Drive) the noise continued. I decided to do some more diagnostics and quickly learned that the car makes the noise at idle with the clutch disengaged as well. So now, I'm convinced it's somewhere in the clutch or TT area. So, that brings me to here!
I bought the following to replace in hopes of fixing the noise:
- LUK Pro Gold LS7 Clutch Kit (LS7 Pressure Plate, Clutch Disk and LS7 Flywheel)
- OEM Slave Cylinder
- OEM Throw Out Bearing
- OEM Pilot Bearing
- Brand New TT Couplers from Zip Corvette (Front and Rear w/ New Hardware)
- Brand New TT Bearings (New Front and New Both Rears)
- OEM Slinger Clip
I have done a ton of reading about the LS7 clutch install (Cobra4B's post being the most convincing -- and that was from years ago
) and I haven't yet been able to really find the answer I'm looking for. Most people that I see install these clutches, they use the LS2 Flywheel (some even us the LS6 Flywheel I've seen). Has anyone used the LS7 Flywheel? I saw one brief response from a gentleman who said he did, that he just had to unbolt the bell housing to help move it back to fit the flywheel in there.
Also, some people say to have the clutch assembly balanced before installation, while others say they just tossed it in there. Is there a definite direction that I should go? Should I remove the old assembly (stock LS6 assembly) and have the LS7 set up balanced as close to that as possible?
Any kind of advice would be greatly appreciated.
Thank you very much.
I hope all is well!
I have a few questions about the LS7 Clutch Install on my 2001 C5 Z06.
Brief rundown/background:
I was running the Z at the local track (the car is stock other than Vararam VR-B2, Borla Stingers and C6Z Shifter). I did a small burn out in the water box to heat/scuff the tires a bit. I launched the car, it drove great, went through all the gears fine, ran 12.9 @ 113 (4200' DA) and got me back to the pits with no problem. When I left the track I had heard a whine/hissing noise coming from the shifter area. It was most prominent (so I thought) when I was driving and in gear. After changing diff fluid and trans fluid (AmsOil Torque Drive) the noise continued. I decided to do some more diagnostics and quickly learned that the car makes the noise at idle with the clutch disengaged as well. So now, I'm convinced it's somewhere in the clutch or TT area. So, that brings me to here!
I bought the following to replace in hopes of fixing the noise:
- LUK Pro Gold LS7 Clutch Kit (LS7 Pressure Plate, Clutch Disk and LS7 Flywheel)
- OEM Slave Cylinder
- OEM Throw Out Bearing
- OEM Pilot Bearing
- Brand New TT Couplers from Zip Corvette (Front and Rear w/ New Hardware)
- Brand New TT Bearings (New Front and New Both Rears)
- OEM Slinger Clip
I have done a ton of reading about the LS7 clutch install (Cobra4B's post being the most convincing -- and that was from years ago
) and I haven't yet been able to really find the answer I'm looking for. Most people that I see install these clutches, they use the LS2 Flywheel (some even us the LS6 Flywheel I've seen). Has anyone used the LS7 Flywheel? I saw one brief response from a gentleman who said he did, that he just had to unbolt the bell housing to help move it back to fit the flywheel in there. Also, some people say to have the clutch assembly balanced before installation, while others say they just tossed it in there. Is there a definite direction that I should go? Should I remove the old assembly (stock LS6 assembly) and have the LS7 set up balanced as close to that as possible?
Any kind of advice would be greatly appreciated.
Thank you very much.
07-08-2016, 01:17 AM
#2
I believe the LS7 flywheel is thicker and heaver which would explain why most use a LS2 flywheel. I just removed a LS7 clutch and replaced it with a Monster LT1-S twin disk. I had the sticking pedal on the track, replaced the master and flushed fluid to no avail. I think the PO did some drag racing which would explain the LS7 failure.
My motor is a crate LS3 so I used it as delivered from Monster. If your engine is stock you should match balance the new flywheel/clutch assembly to the old. Be sure to mark everything before taking it apart and take lots of pictures.
Add a remote bleed hose while it's apart, makes bleeding the slave cylinder much easier.
Good luck.
My motor is a crate LS3 so I used it as delivered from Monster. If your engine is stock you should match balance the new flywheel/clutch assembly to the old. Be sure to mark everything before taking it apart and take lots of pictures.
Add a remote bleed hose while it's apart, makes bleeding the slave cylinder much easier.
Good luck.
Last edited by danh52; 07-08-2016 at 01:17 AM.
The following users liked this post:
SNL/MonsterClutchCo (07-26-2016)
07-08-2016, 08:40 AM
#3
Le Mans Master
Balanced and shimmed or NOT shimmed... which ever the case may be
07-20-2016, 09:29 PM
#4
Instructor
Thread Starter
I believe the LS7 flywheel is thicker and heaver which would explain why most use a LS2 flywheel. I just removed a LS7 clutch and replaced it with a Monster LT1-S twin disk. I had the sticking pedal on the track, replaced the master and flushed fluid to no avail. I think the PO did some drag racing which would explain the LS7 failure.
My motor is a crate LS3 so I used it as delivered from Monster. If your engine is stock you should match balance the new flywheel/clutch assembly to the old. Be sure to mark everything before taking it apart and take lots of pictures.
Add a remote bleed hose while it's apart, makes bleeding the slave cylinder much easier.
Good luck.
My motor is a crate LS3 so I used it as delivered from Monster. If your engine is stock you should match balance the new flywheel/clutch assembly to the old. Be sure to mark everything before taking it apart and take lots of pictures.
Add a remote bleed hose while it's apart, makes bleeding the slave cylinder much easier.
Good luck.
Bump! Anyone use the full LS7 setup?!
07-25-2016, 12:57 PM
#5
Instructor
It was my understanding that everyone using an LS7 clutch assembly was using either the LS7 flywheel or an aftermarket lightweight flywheel. I thought it was because the LS7 flywheel was a certain shape (recessed in the middle). If you look at the various vendor websites and for-sale threads you can see they configure the LS7 flywheel with the LS7 clutch as an upgraded clutch option for C5's.
Like you, I am also slightly confused because it seems the aftermarket lightweight flywheels are not a special design which would accommodate the LS7 clutch- yet people seem to be using this configuration also.
Regarding the balancing, I have read many posts from a fellow member "thbwlz" who has done extensive investigation about the proper balancing protocol. The bottom line is that you will want to replicate whatever balance your factory clutch/flywheel assembly has. If you do not do this you can introduce new vibrations by ignoring the factory flywheel balancing GM performed as a fine-tuning procedure specific to corvettes. Keep in mind you are replicating the FACTORY balancing specs, so if your clutch/FW has been replaced or re-installed at any time in the past your odds of even currently having the OEM balancing spec are slim.
If all of those things check out you will need to mark your pressure plate and flywheel in relation to each other as well as in relation to the crankshaft PRIOR TO REMOVAL. Then take your old and new assemblies to a machine shop and have them replicate the balancing.
Hope this helps. Just as a disclaimer, I am not speaking from actual experience. I am repeating what I have read in my research over the past weeks since I am also going through the process of replacing my clutch.
Like you, I am also slightly confused because it seems the aftermarket lightweight flywheels are not a special design which would accommodate the LS7 clutch- yet people seem to be using this configuration also.
Regarding the balancing, I have read many posts from a fellow member "thbwlz" who has done extensive investigation about the proper balancing protocol. The bottom line is that you will want to replicate whatever balance your factory clutch/flywheel assembly has. If you do not do this you can introduce new vibrations by ignoring the factory flywheel balancing GM performed as a fine-tuning procedure specific to corvettes. Keep in mind you are replicating the FACTORY balancing specs, so if your clutch/FW has been replaced or re-installed at any time in the past your odds of even currently having the OEM balancing spec are slim.
If all of those things check out you will need to mark your pressure plate and flywheel in relation to each other as well as in relation to the crankshaft PRIOR TO REMOVAL. Then take your old and new assemblies to a machine shop and have them replicate the balancing.
Hope this helps. Just as a disclaimer, I am not speaking from actual experience. I am repeating what I have read in my research over the past weeks since I am also going through the process of replacing my clutch.