[Z06] LS7 Clutch Install, Torque Tube Rebuild, Leaky Butt Fix Notes
04-21-2014, 07:48 AM
#1
Racer
Thread Starter
LS7 Clutch Install, Torque Tube Rebuild, Leaky Butt Fix Notes
Thought I would share a few notes on these mods all of which I did in the last few days. Most of this is old news that I got off the forum, but some of it I had to dig a bit.
To get the LS7 pressure plate in, you have to hammer in the locating dowels that are on the LS7 flywheel. This provides clearance to get the PP in without loosening up the 5 bell housing bolts. You MUST HAVE a plan regarding the pilot bearing. I got loaned a PB puller and it would not budge until I sprayed a can of contact cleaner on it to "freeze" the PB and then in came out real quick. Before that, no movement. Going in, freeze the pilot bearing, then hammer it in with a block of wood.
I took off the rear cradle, the diff, trans, and torque tube all in one go. My friend had a lift so, I thought it was all easy street. Not so, you need about four jacks to complete the job, preferably two tranny jacks. Once all that is removed you must support the engine so it does not hit the firewall. Two jacks were necessary to drop the rest of the assembly. Definitely take off the shifter. I heard it was optional, but it got stuck practically the whole time. Two minutes would have saved 30...
Because I was doing the leaky butt fix, I took off the rear cradle (once down) and then the diff. There is a sneaky nut under neath the rear end that connects it to the trans (MT). Also, the output shaft seal housings on the diff could not be removed without removing the diff from the trans (at least not the left one). The replacement seals were considerably different than the originals. I got them from Patrick at GM Parts House who never steered me wrong so, looks like they will fit after much deliberation. They are a bit smaller outside diameter (the lip) and they don't go in as deep (the rubber) but you have to remember the axle is going in there and there is plenty of beef either side of the rubber.
The torque tube, as they say, get the biggest damn circlip pliers you can find, and from my estimation, go one size bigger. It was tough. The 12mm bolts on the couplers were hella hard to get off. We sheared off one torx bit, and bent another one. The factory loctite is strong! We used wood and hammer to seat all the bearings. If we were smarter we could have used the shop press to put the bearings on before reassembly to the propeller shaft but oh well. A few bits of randomly sized pipe would have helped... My couplers were fine at 90k miles which I was surprised. I went with the RPM poly couplers which look robust to say the least.
On reassembly, we put the TT on the transmission, and lifted just that up and sent it home into the clutch. This was lighter and easier, but still required several jacks, three people, and some cussing and luck. Make sure you are thinking about where the wire loom above the TT is going. Next we attached the rear end. This gave us time to properly rearrange our jack strategy. Next went the rear cradle. Don't forget to put the half shafts in place. We left them forward, and had to drop the cradle a second time, had a jack in the wrong place and the whole thing dropped like 8" but not lower that allowable according to the diagram on the TT.
Tomorrow, we button it all up, hope for the best, and away we go. I will post pics after it's all done. Big job, $1500 for all the parts, tools, and lubes. But I think it would have been $3k at a shop so...
To get the LS7 pressure plate in, you have to hammer in the locating dowels that are on the LS7 flywheel. This provides clearance to get the PP in without loosening up the 5 bell housing bolts. You MUST HAVE a plan regarding the pilot bearing. I got loaned a PB puller and it would not budge until I sprayed a can of contact cleaner on it to "freeze" the PB and then in came out real quick. Before that, no movement. Going in, freeze the pilot bearing, then hammer it in with a block of wood.
I took off the rear cradle, the diff, trans, and torque tube all in one go. My friend had a lift so, I thought it was all easy street. Not so, you need about four jacks to complete the job, preferably two tranny jacks. Once all that is removed you must support the engine so it does not hit the firewall. Two jacks were necessary to drop the rest of the assembly. Definitely take off the shifter. I heard it was optional, but it got stuck practically the whole time. Two minutes would have saved 30...
Because I was doing the leaky butt fix, I took off the rear cradle (once down) and then the diff. There is a sneaky nut under neath the rear end that connects it to the trans (MT). Also, the output shaft seal housings on the diff could not be removed without removing the diff from the trans (at least not the left one). The replacement seals were considerably different than the originals. I got them from Patrick at GM Parts House who never steered me wrong so, looks like they will fit after much deliberation. They are a bit smaller outside diameter (the lip) and they don't go in as deep (the rubber) but you have to remember the axle is going in there and there is plenty of beef either side of the rubber.
The torque tube, as they say, get the biggest damn circlip pliers you can find, and from my estimation, go one size bigger. It was tough. The 12mm bolts on the couplers were hella hard to get off. We sheared off one torx bit, and bent another one. The factory loctite is strong! We used wood and hammer to seat all the bearings. If we were smarter we could have used the shop press to put the bearings on before reassembly to the propeller shaft but oh well. A few bits of randomly sized pipe would have helped... My couplers were fine at 90k miles which I was surprised. I went with the RPM poly couplers which look robust to say the least.
On reassembly, we put the TT on the transmission, and lifted just that up and sent it home into the clutch. This was lighter and easier, but still required several jacks, three people, and some cussing and luck. Make sure you are thinking about where the wire loom above the TT is going. Next we attached the rear end. This gave us time to properly rearrange our jack strategy. Next went the rear cradle. Don't forget to put the half shafts in place. We left them forward, and had to drop the cradle a second time, had a jack in the wrong place and the whole thing dropped like 8" but not lower that allowable according to the diagram on the TT.
Tomorrow, we button it all up, hope for the best, and away we go. I will post pics after it's all done. Big job, $1500 for all the parts, tools, and lubes. But I think it would have been $3k at a shop so...
04-21-2014, 11:10 PM
#2
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Could you clarify your clutch install a little, like how to avoid any problems? I am right now at the point of sliding the drive train out of the engine in order to repair a broken pressure plate. Does the PB always have to come out, as in time limited parts?
Do you have a source for parts? It looks like the whole clutch ***'y. has to be replaced, including the flywheel, according to the manual.
How spendy are the specialty tools, like the PB puller and quick disconnect remover for the clutch hydro hose?
TIA
jim
Do you have a source for parts? It looks like the whole clutch ***'y. has to be replaced, including the flywheel, according to the manual.
How spendy are the specialty tools, like the PB puller and quick disconnect remover for the clutch hydro hose?
TIA
jim
04-22-2014, 07:30 AM
#3
Racer
Thread Starter
Could you clarify your clutch install a little, like how to avoid any problems? I am right now at the point of sliding the drive train out of the engine in order to repair a broken pressure plate. Does the PB always have to come out, as in time limited parts?
Do you have a source for parts? It looks like the whole clutch ***'y. has to be replaced, including the flywheel, according to the manual.
How spendy are the specialty tools, like the PB puller and quick disconnect remover for the clutch hydro hose?
TIA
jim
Do you have a source for parts? It looks like the whole clutch ***'y. has to be replaced, including the flywheel, according to the manual.
How spendy are the specialty tools, like the PB puller and quick disconnect remover for the clutch hydro hose?
TIA
jim
More Notes
When reinstalling, make sure the axles are more or less in place, not forward. We had to drop the cradle a second time. Also, you cannot get the lower bolt in the e-brake bracket unless you put it in before reinstalling the upper A-arm. The rectangle wire loom above the torque tube needed to be pushed back toward the rear of the car a couple inches for all the tranny/diff connections to fit without cause for alarm. I put the shifter in and it was not shifting. I took it out, reinstalled, and whammo it was good to go. Be careful not to drop any tools by the shifter. I dropped a 1/4 ratchet and 10m socket and had to re-lift, remove the exhaust x pipe, and the 56 bolt panel to get it out. WTF. Cheers and good luck!
04-23-2014, 12:30 AM
#4
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I called Napa Auto Parts and the tool for doing the clutch line that is listed in the manual is for dealers only, but they found an aftermarket one for $7. We'll see tomorrow. I'm wondering why nobody talks about spilled fluid from the line. Do they seal off when disconnected? Another thing: I can't get the line loose from up by the engine. WTF kind of bracket is this? 
Also in case the tool is worthless could you be a little more specific about getting the line apart?
I also have a 4 post lift, and I put a plate across the ramps under the engine, under the tranny, and under the torque tube. The ***'y. is coming out nicely but I need to get the stupid clutch line apart. I have a floor jack under the tranny, a jack stand under the tt., and a bottle jack under the oil pan. But not in this pic.
Also in case the tool is worthless could you be a little more specific about getting the line apart?I also have a 4 post lift, and I put a plate across the ramps under the engine, under the tranny, and under the torque tube. The ***'y. is coming out nicely but I need to get the stupid clutch line apart. I have a floor jack under the tranny, a jack stand under the tt., and a bottle jack under the oil pan. But not in this pic.
04-23-2014, 12:52 AM
#5
Racer
Thread Starter
I called Napa Auto Parts and the tool for doing the clutch line that is listed in the manual is for dealers only, but they found an aftermarket one for $7. We'll see tomorrow. I'm wondering why nobody talks about spilled fluid from the line. Do they seal off when disconnected? Another thing: I can't get the line loose from up by the engine. WTF kind of bracket is this? Also in case the tool is worthless could you be a little more specific about getting the line apart?
I also have a 4 post lift, and I put a plate across the ramps under the engine, under the tranny, and under the torque tube. The ***'y. is coming out nicely but I need to get the stupid clutch line apart. I have a floor jack under the tranny, a jack stand under the tt., and a bottle jack under the oil pan. But not in this pic.
Also in case the tool is worthless could you be a little more specific about getting the line apart?I also have a 4 post lift, and I put a plate across the ramps under the engine, under the tranny, and under the torque tube. The ***'y. is coming out nicely but I need to get the stupid clutch line apart. I have a floor jack under the tranny, a jack stand under the tt., and a bottle jack under the oil pan. But not in this pic.
04-23-2014, 07:07 PM
#6
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Swear to God, i just worked the white plastic down with my thumb and forefinger and it came loose... Keep trying. Don't know why you'd want to take it off further up... Near the master??? Just do the quick disconnect. Yes, it does seal off when you take it apart. Very little fluid comes out.
jim