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Drew, I understand you are familiar with the car but I am sure it is there, did a ton of research about this (the pic is from the shop manual). If you have not dealt with it before you may have over-looked it as part of the trans housing. Steve I hope it works out but I think you will be pulling the trans back out again, JMHO.

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ArizonaBOSS

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I'm not 100% confident but I don't think I saw that thing on my trans. Also that is the 2011 service manual on IIHS. If they did eliminate the spacer in 2012 it wouldn't be shown in there.
 
ArizonaGT said:
I'm not 100% confident but I don't think I saw that thing on my trans. Also that is the 2011 service manual on IIHS. If they did eliminate the spacer in 2012 it wouldn't be shown in there.

Actually the 2011 manual has the Boss included in it. We figured that out when rebuilding my engine. I was surprised but remember the first 12's were made in 2/2011. If there is a difference between the Boss and GT or V6 it will mention this. Plus our cars were not built too far apart even if they made a change but again I am sure about the spacer.
 

steveespo

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The only thing I can go by is the distance from the pilot shaft tip to the face of the throw out bearing, which is exactly the same on the GT trans with spacer and the Boss trans without the spacer. If I add the spacer it closes that dimension down by 7/16" which could make the diaphragm get pushed in to far and go over center which definitely makes the pedal stick to the floor. I'm gonna go with no spacer, if it doesn't disengage the clutch fully, well then I know how to do this job easy now and will do it twice. I figure the McLeod clutch is designed specifically as a GT replacement(6 bolt pressure plate) using the stock slave/TOB so the throw distance to disengage should be the same as the GT. maybe the Boss clutch required more throw to release so the preset distance is less? Or not? I did figure out the V6 cars don't have a spacer from '11 on, I was afraid that I got duped and sold one but cross referenced the trans tag and CR33-7003-AB is a 2012 5.0L Boss or GT transmission. Scott check the trans tag number on the right side of the rear of the trans on yours for me if you get a chance, if it's a BR33 or CR33-7003-AA number then you may have a different casting that requires the spacer.

Car companies always find ways to complicate things that should be simple.
Thanks again for all the input.
Steve
 
steveespo said:
cross referenced the trans tag and CR33-7003-AB is a 2012 5.0L Boss or GT transmission.

That is the point same trans and block. Even the slave is the same. There may be a difference in the height of the clutch but often that is minimum, for example Exedy single disc is 72.75mm and the twin 73.2mm, that is within build tolerances. It is not easy to understand all of this, the example of how the 302R compared to my setup is proof but as long as you understand you may need to pull the trans again it's all good. When we had the spacer issue wrong on mine it would work on the street, grabbed high but still worked, but as soon as I tracked and heated it up it would do the opposite and go to the floor.
 

steveespo

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Drew, I wish I could withdraw from it too :eek: All I can fall back on is the distance that the TOB is in relation to the input shaft. Worse comes to worst I have to pull it apart to install the spacer but just seems that it would compress the slave a lot more than I had it with the stock set up. I value Scott's opinion highly so I still have a decision to make this Saturday when it goes in. Anybody have tricks to re bleed the new slave, I plan on filling the master cylinder reservoir with my finger over the clutch hose, let some drain down by gravity and quickly snap it into the fitting. Still leaves the volume inside the slave to get the air out of. I have the mighty vac and the rubber stopper to vacuum it like the manual shows. 50 pumps of the pedal should do it right?
Steve
 

ArizonaBOSS

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Sounds like you are off to a good start--you can probably cap off the line ASAP once you pull it out of the trans as well by using one of the brembo bleeder covers or something like that.

Other than that, jack up the driver's corner of the car and pump the clutch 11ty million times. Mine worked fine even w/o the mityvac but that's always good insurance.
 

ArizonaBOSS

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Steve can you provide us a couple of clear pictures of each transmission's mounting flange for the slave/TOB? That might help us speculate more, lol
 
ArizonaGT said:
I officially withdraw myself from this conversation :) I just can't say for certain one way or the other with all this info being thrown around.

I learned by experience on this and still I have little knowledge about it all. What I have found is what works for me since after a long time a lot of money and several paid for but missed track days we figured it out. When I first pulled my trans out to replace the slave I did not notice the spacer. I even said there was not one in there to my friend and he assured me it was there. The second time we pulled it and I was looking for it, sure enough it was there. I am not faulting Steve's thinking by measuring, I guess we will find out if there is a difference.

Steve, my trans is a BR33-AH but without the blueprints is it not going to tell us much. Since you have the two transmissions have you measured the length of the input shaft on both and the bellhousing height? If there is a difference in those measurements it would explain a lot. As far as bleeding there is no special trick, we have been bleeding with vacuum on my car since my friend has the proper tools but when I ask the race team how they do it, they point to the junior guy on the team who sits in the car and pumps the clutch. I have also had to do this at the track sometimes.
 

steveespo

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Scott, thanks for checking the tag, BR33-AH makes some sense, since your car was a very early 2012 build, mine was a BR33-AA September 2010 build. I think they changed the casting of the front bearing supporNdola the CR33 series and eliminated the spacer. I did measure the bellhop sing, straightedge across the face and the pilot shaft sticks 6mm past and the distance to the mounting face of the throw out bearing is exactly the same. I'm going with no spacer and hopefully I'm right, if not I can do this job in 4 hours now.

I have searched the net looking for confirmation but there is nothing out there, I'll try and call or visit a Ford dealer to see if they can verify in their parts computer.
Steve
 
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The way you guys eat clutches maybe it's time for one of these.......It seems like only a matter of time before you send parts through the floor pan

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