Help with 3-4 synchro
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Joined: Jan 2003
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From: Birmingham, AL
Help with 3-4 synchro OK this thing is from a 99 Vette T56. I'm pretty sure I've got it put together correctly. It was marked before I took it apart and cleaned it. I added billet keys and new springs. The half on the right has a ring that the internal gear won't go through. I'm assuming this goes on the 4th gear side of the mainshaft? Also, I know there are arrows on the blocker rings. What are they for? I'm sure aligning but with what? Also, one side of the hub is tapered. Which way does that go? Thanks in advance. Below is a picture of how I believe it goes. I swear I took plenty of pictures, just not of the synchro before I took it apart. 
The rings you have there are for 1/2 not 3/4. 4th is the syncro teeth on the input shaft. 3rd above that then 2nd then 1st. 4th is only one ring. 1 and 2 use a couple rings.
I just noticed you are using an older trans. I guess they changed it up a little. But the order should be pretty much the same.
I just noticed you are using an older trans. I guess they changed it up a little. But the order should be pretty much the same.
The rings you have there are for 1/2 not 3/4. 4th is the syncro teeth on the input shaft. 3rd above that then 2nd then 1st. 4th is only one ring. 1 and 2 use a couple rings.
I just noticed you are using an older trans. I guess they changed it up a little. But the order should be pretty much the same.
I just noticed you are using an older trans. I guess they changed it up a little. But the order should be pretty much the same.
OK this thing is from a 99 Vette T56. I'm pretty sure I've got it put together correctly. It was marked before I took it apart and cleaned it. I added billet keys and new springs. The half on the right has a ring that the internal gear won't go through. I'm assuming this goes on the 4th gear side of the mainshaft? Also, I know there are arrows on the blocker rings. What are they for? I'm sure aligning but with what? Also, one side of the hub is tapered. Which way does that go? Thanks in advance. Below is a picture of how I believe it goes. I swear I took plenty of pictures, just not of the synchro before I took it apart.
Thread Starter
TECH Enthusiast
Joined: Jan 2003
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From: Birmingham, AL
Thanks guys for the posts. I was trying to figure out why one side had a lip on it that wouldn't allow the inner most gear to slide through but one side didn't. Also, can you tell me about the arrow on the blocker ring itself? And last, how about the correct direction of the beveled edge of the slider. I've been told it doesn't matter but they didn't put that bevel there for no reason. Thanks again!
Thanks again! Thanks guys for the posts. I was trying to figure out why one side had a lip on it that wouldn't allow the inner most gear to slide through but one side didn't. Also, can you tell me about the arrow on the blocker ring itself? And last, how about the correct direction of the beveled edge of the slider. I've been told it doesn't matter but they didn't put that bevel there for no reason. Thanks again!
Thanks again!As for the bevel, all the original vette transmissions I have taken apart have the bevel facing the rear of the transmission. That is the way I re-install them but I am pretty sure it doesn't matter either way. At one point in time vette syncro's were out of stock so we used f-body outer sliders on the vette inner hub. The f-body slider wasn't beveled on either side.
Also, the outer blocker rings look scuffed as if the friction cones are worn to their limits. Were you planning to re-use those blockers/friction cones?
And...there is a thick thrust washer that goes next to third gear before you slide the blockers on there. Make sure you don't forget that.
And...there is a thick thrust washer that goes next to third gear before you slide the blockers on there. Make sure you don't forget that.
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Thread Starter
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From: Birmingham, AL
Jonathan, how can I measure to see if it's worn too much? These vette synchros aren't in the Tremec manual If I put the third gear side together with the thrust washer and all components, the blocker ring sits against the gear. Is this normal or should it be just off the gear? If it is too worn, can you buy individual pieces or do you have to buy an entire synchro assembly?
If I put the third gear side together with the thrust washer and all components, the blocker ring sits against the gear. Is this normal or should it be just off the gear? If it is too worn, can you buy individual pieces or do you have to buy an entire synchro assembly? Last edited by WS6 GreeN; Aug 1, 2012 at 10:21 PM.
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I'm obviously no Jon here but maybe i can help lol. Your saying if you take the blocker ring by itself and put it onto the gear cone it bottoms out and touches the gear? if this is the case and the blocker ring is new then the friction cone on the gear is worn out and needs to be replaced tremec recommends .020 clearance between the block and gear.
By bottoming out on the gear the blocker ring will not synchronize correctly and grind. i just did this on my tranny 3rd gear would grind a lot on the downshift even after my rebuild and it looked fine to the naked eye and it even had a touch over .020 clearance but it did sit lower on the gear than any other gear so I replaced 3rd gear and the synchro assembly and all seems to be well now.
By bottoming out on the gear the blocker ring will not synchronize correctly and grind. i just did this on my tranny 3rd gear would grind a lot on the downshift even after my rebuild and it looked fine to the naked eye and it even had a touch over .020 clearance but it did sit lower on the gear than any other gear so I replaced 3rd gear and the synchro assembly and all seems to be well now.
As was mentioned the contact on the face of the blocker ring indicates a complete wear out condition. New/ acceptable parts will not contact the gear face when loaded.
The mark you see on the parts is not an arrow. It is a vendor ID mark and has no bearing on assembly.
The mark you see on the parts is not an arrow. It is a vendor ID mark and has no bearing on assembly.
