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Discussion Starter #1 (Edited)
I've had my LS7 clutch slipping in the 6th around 2krpm for a couple of month. Then it started slipping even in the 4th
So I thought - OK, maybe I have another month before it's completely done, but no - I was going to a store 3 miles away and it started slipping badly -3rd then second. I turned around and didn't even make it to the house - stopped two blocks away - no grabbing whatsoever. Stank to high heaven.
I wasn't expecting it to go that quickly - from holding the 4th gear to a complete standstill in 5 min. I thought it would still grab a little or make noises or something - not act like it's completely missing...
Pedal travel never changed and reservoir was full.
I'm getting it replaced with Monster's dual disk LT1-S, but I will have limited shop time, so I need to have all possible parts on hand when it happens.
It got me thinking - what if my rear seal started leaking or my slave gave out? Should I worry about it?
Another question I'm curious about - do I need to also replace the pilot bearing?? Why is it necessary and will it be included in the package?
 

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I would, and did replace the rear main seal and pilot bearing when I did my clutch, slave of course too. But I didn't have limited shop time.

The questionable aspect of doing the pilot bearing time wise will be getting the old one out. Don't even mess with the ones you tighten down then turn the wingnut to extract them. Get a bearing puller that uses a big slide hammer. Installing the new one takes less than a minute.

As for the rear main seal, I've read of guys on here who had the new one leak right away because they didn't use an alignment tool when putting the housing back on. I guess if you leave the housing on and only replace the seal that would prevent that problem. What I did was buy an oem housing with a new seal already in it, then when I put it on I used rtv along the bottom and tightened all the bolts to the block before I tightened the ones to the oil pan. My thought was that if you tighten the oil pan bolts too soon then it might pull the housing downward and pull the seal off center. It hasn't started leaking yet but if I had to do it again I'd get the alignment tool and make sure it was centered. I think it's made by saccity Corvette.
 

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When I did my clutch I just replaced the rear main seal, not the entire cover. It is dry as a bone. To me, changing just the seal seems easier and less risky.

Don't forget to install a remote slave bleeder while you have it all apart.
 

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I've had my LS7 clutch slipping in the 6th around 2krpm for a couple of month. Then it started slipping even in the 4th
So I thought - OK, maybe I have another month before it's completely done, but no - I was going to a store 3 miles away and it started slipping badly -3rd then second. I turned around and didn't even make it to the house - stopped two blocks away - no grabbing whatsoever. Stank to high heaven.
I wasn't expecting it to go that quickly - from holding the 4th gear to a complete standstill in 5 min. I thought it would still grab a little or make noises or something - not act like it's completely missing...
Pedal travel never changed and reservoir was full.
I'm getting it replaced with Monster's dual disk LT1-S, but I will have limited shop time, so I need to have all possible parts on hand when it happens.
It got me thinking - what if my rear seal started leaking or my slave gave out? Should I worry about it?
Another question I'm curious about - do I need to also replace the pilot bearing?? Why is it necessary and will it be included in the package?
The take away here is never gamble on consumable car parts. What probably happened was it slipped enough to totally glaze the plate or the friction material wore down to the rivets so on one side or both it was metal to metal. When a disk starts to slip it turns into a grinding wheel and eats itself. If the slave is not blown the pedal will remain the same. When you get into a job like a clutch it is wise to replace every part that has the potential to fail causing you to take the whole thing apart again Pulling the tranny a second time is not fun standing on one foot while you are kicking yourself in the ass with the other cause you didn't spring for a $30 pilot the first time around. Slave, clutch, pressure plate, flywheel, pilot bearing and cover with seal are the basics, a cover with seal installed is best if you don't have the knowledge and/or tooling for a seal alone job. I recommend a sealed pilot bearing, the solid are asking for trouble and there are 2 bearing sizes avalibal, a corvette part O.D. is bigger and won't work. I modified a lifter puller to pull the bearing. The slaves also come in more than one size fits all if you use the plastic 'alinement tool' that comes with clutch kits apply upward pressure to it when pulling down the pressure plate bolts, otherwise it droops and the input shaft probably won't line up, the best bet is using an actual input shaft if you can find one. If you don't have one now take the opportunity to install a remote slave bleed line, you will be glad when you flush the system after 6-700 miles and find the fluid blacker than the inside of your hat. You will need 2' of 1/2" extension and a universial joint, the socket size I do not recall. If there is an after market shifter in your future do it now, trust me on that one.
 

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I've had my LS7 clutch slipping in the 6th around 2krpm for a couple of month. Then it started slipping even in the 4th
So I thought - OK, maybe I have another month before it's completely done, but no - I was going to a store 3 miles away and it started slipping badly -3rd then second. I turned around and didn't even make it to the house - stopped two blocks away - no grabbing whatsoever. Stank to high heaven.
I wasn't expecting it to go that quickly - from holding the 4th gear to a complete standstill in 5 min. I thought it would still grab a little or make noises or something - not act like it's completely missing...
Pedal travel never changed and reservoir was full.
I'm getting it replaced with Monster's dual disk LT1-S, but I will have limited shop time, so I need to have all possible parts on hand when it happens.
It got me thinking - what if my rear seal started leaking or my slave gave out? Should I worry about it?
Another question I'm curious about - do I need to also replace the pilot bearing?? Why is it necessary and will it be included in the package?
when it starts slipping when fully engaged, it's done, period. it could be for multiple reasons, from clutch contamination from something like oil to failure of a specific part, or it's just worn out to the point where it can no longer maintain enough clamping force.

lt1-s install is a breeze, btw.

you'll see if the rear seal is leaking when you pull the flywheel off. slave and pilot bearing you should always replace anyway with a new clutch install. clutch disk dust gets past the slave cyl seal and gets in the system, and you never want to run the car with a bad pilot bearing. always go new on those parts.

I would, and did replace the rear main seal and pilot bearing when I did my clutch, slave of course too. But I didn't have limited shop time.

The questionable aspect of doing the pilot bearing time wise will be getting the old one out. Don't even mess with the ones you tighten down then turn the wingnut to extract them. Get a bearing puller that uses a big slide hammer. Installing the new one takes less than a minute.
+11ty. blind hole puller. even a cheap one from harbor freight. and get a seal installer/driver set to put the new one in.

What I did was buy an oem housing with a new seal already in it, then when I put it on I used rtv along the bottom and tightened all the bolts to the block before I tightened the ones to the oil pan. My thought was that if you tighten the oil pan bolts too soon then it might pull the housing downward and pull the seal off center. It hasn't started leaking yet.
that is a perfectly acceptable way to do it. using the tool is better because it doesn't flex like the seal could when you're tightening things down, but as long as the cover doesn't budge when you tighten the oil pan bolts, you should be ok.
 

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Totally agree on the remote bleeder. I also installed a monster stainless braided pressure line and 3' remote bleeder when I did mine last winter. I've got about 6k on it now and just bled it recently, as mentioned very dirty from the new clutch break in.

I didn't really know where to route the bleeder line so I just routed it up near the clutch master cyl, but when I bled it I just did a gravity bleed since it was just me. Thinking about running down near the oil filter, I was able to snake it between the oil pan and steering linkage to keep it away from the exhaust. I think I read on here that someone bleeds theirs every oil change. I hope it's not that often but if that's necessary at least it will be easily accessible while I'm changing the oil.
 

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Totally agree on the remote bleeder. I also installed a monster stainless braided pressure line and 3' remote bleeder when I did mine last winter. I've got about 6k on it now and just bled it recently, as mentioned very dirty from the new clutch break in.

I didn't really know where to route the bleeder line so I just routed it up near the clutch master cyl, but when I bled it I just did a gravity bleed since it was just me. Thinking about running down near the oil filter, I was able to snake it between the oil pan and steering linkage to keep it away from the exhaust. I think I read on here that someone bleeds theirs every oil change. I hope it's not that often but if that's necessary at least it will be easily accessible while I'm changing the oil.
I flush the brakes and clutch annualy, fluid is discolored but still transparent, DOT4 is cheap. Every oil change seems a bit excessive. I put heat shrink over the bleed fitting and just zip it to the rail but I use an 18" line. It helps a little if you keep the end of the line below the slave level. There is a way to one man bleed things if you are interested.
 

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There is a way to one man bleed things if you are interested.
Other than just opening up the bleeder and letting it run while keeping the res. full? That's how I did it when I installed it all, and after doing the same thing the other day it seemed to have a good pedal feel. Though I didn't drive it because it's still on jack stands waiting to get the rotors back so I can finish up the ctsv brake upgrade.
 

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Discussion Starter #11 (Edited)
OK, so I found the rear cover w/seal - Dorman 635518 for $35 at StoneAuto
I won't need to drop the pan for this like Service Manual suggests, right?

Alignment tool from Saccity for $47 on Ubay

I'm not sure if I need a remote bleeder - I might already have one - how would I know without jacking the car up - where do I look for it? somewhere by the master? Which one's better- Hinson, Tick or something else? How do I choose one?

I'm going to replace the pilot bearing with the one that comes with the clutch -must be a good one, right?
I watched the bread trick removal video on youtube - looks legit, has anyone tried that successfully? If not - I'll borrow the slide hammer and pulley remover from O-really, or buy one at HoboFreight for $73

I'll get the slave from Duckman with the clutch - not sure what brand, but he sells one for $85
Do I have to worry about distances and tolerances with Monster products - measuring for possible shims?

I've seen people advising to replace the oil galley barbell with a billet one from Saccity while I'm at it - only $25. Is this a good idea generally?

I think that's about it and all the bases are covered, or am I missing something? Are there any tips or tricks I need to know before dropping the tranny?

Oh, yeah, and I do have a short-throw shifter already, but it makes noises (rattles) and there is no heat/sound-proofing cover under it, so I hate it. I almost want to go back to stock because of the road/tranny noise and heat. AFAIK, all aftermarket short shifters have this issue, right?
 

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The tool is used without the seal installed in the cover, iirc. You should buy the seal seperate.

Don't use the bread trick. You will regret it.
 

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Discussion Starter #13
The tool is used without the seal installed in the cover, iirc. You should buy the seal seperate.

Don't use the bread trick. You will regret it.
You're saying I can't remove the seal and then push it in later? Why would I regret the bread trick? - I want to try it really bad - You tried it and it didn't work?
 

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A guy recently did the bread trick and ended up punching through the block somehow. Maybe it was the crank - I don’t know really but he ended up pulling a sandwich worth out of his pan.
 

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There's a plug in the crank that will just fall in the oil pan or something. It's just unique to these cranks, not a knock on that method per se.

Look up that saccity tool on YouTube to see how it's used. It basically mimics the shape of the seal between the crank and the cover while you bolt down the cover, then you pull it out and use it as a seal installer. So if you want to put a new barbell in then you'll have to take the cover off, which will negate the current seal alignment. But if you buy a new cover with a seal already installed then you'll have to remove it without damaging it to use the alignment tool. Now that I think about it, why even replace the cover? I can't really remember why I did, I guess just because the seal was already installed but I bought it before I knew about the alignment thing. I also didn't know about the barbell either

Also as a side note, you don't use any oil on the new seal for some reason. It can cause leaks
 

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Discussion Starter #16
Yeah, I guess I'll just do the seal alone. And yes - the service manual talks about using some oil on the outside diameter, but not on the surface or the inside diameter.
Thanks everyone for your feedback!
 

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Other than just opening up the bleeder and letting it run while keeping the res. full? That's how I did it when I installed it all, and after doing the same thing the other day it seemed to have a good pedal feel. Though I didn't drive it because it's still on jack stands waiting to get the rotors back so I can finish up the ctsv brake upgrade.
Need a clear glass vessel with lid (like a quart size pickle jar) 1/4" and 5/16" clear vinyl tubing and fluid. Poke a hole in the center of the lid for the 1/4" tubing, it has to reach the bottom of the jar and stay there, use whatever you have handy to make it so, I've been known to use lead fishing weights. Pour 1"-1 1/2" of fluid into the jar; the tube must remain submerged and you will probably need the weight to keep from tipping over. Set the jar where it can be seen well from the drivers seat and below the level of the piece you are bleeding. Cut the other end square and push it on to the bleeder nipple; you may have to find a manner to keep it upright and/or use a little bit of grease (do not get grease into the fluid, if it finds it's way into the system bad things can happen) or go to the pet store for some air line tubing, not the clear (you already have that) the black or green and a butt connector, that stuff is much softer. The point is to keep that connection sealed. Top the resivior, crack the bleeder and pump the peddle all the way to the floor (3 times for brakes, 2 for clutch. Half that if the system is dry) observe the tubing submerged in the jar and pay attention to the resivior levels, when no more bubbles come out you're done, close the bleeder and call it a day. (if you get streams of tiny bubbles you are sucking air somewhere) It all sounds very complicated and time consuming but in practice it will take a lot more time to get the wheel off than to bleed. The trick is in keeping air from entering the tubing from outside, you have to maintain a seal like a closed system, that is why one end is submerged, the other a tight fit. Tips: If you use the aquarium tubing you can do without the 5/16", the nipple on the front calipers is larger than the rear but the fish tank tube is soft enough to stretch it. If you go 5/16" you will have to somehow connect it to the 1/4" or run a separate line. The vinyl gets stiff after a while, lay it in the sun will make it soft again or just replace it. If you decide to keep the rig for next time either store it dry or be sure the open end of the line is higher than the jar; even if the tube appears empty and dry some how the fluid will find a way to siphon out, I don't know how, it just does and very quickly. You can build the whole rig for less than a buck (not including the pickles) you don't have fluid everywhere, when you get the hang of it you can hit all 4 corners and the clutch in 5 minutes or less and don't have to recruit anyone (like the wife) who may or may not know what they are supposed to do.
 

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Bread can end with a lot more bread; there is an oil gallery that runs the lenght of the crank, for some reason GM left the end open with just a soft plug. The bread thing is hydraulic so the weakest point is going to give, blow that plug it goes into the crank, disrupts the oil system and locks the motor quicker than you can read this.
 

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Other than just opening up the bleeder and letting it run while keeping the res. full? That's how I did it when I installed it all, and after doing the same thing the other day it seemed to have a good pedal feel. Though I didn't drive it because it's still on jack stands waiting to get the rotors back so I can finish up the ctsv brake upgrade.
Until you run the motor it will feel like a good peddle, vacuum assist can be a different story.
 
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