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JT15601
12-26-2013, 01:25 PM
So I'm I'm the process of rebuilding my M5R2 and I'm replacing the old fiber lined ones with the brass ones and adding the friction modifier and all that fun stuff. At any rate, each of the 4 larger old sychros has one tooth missing and my new ones don't have one missing. The old reverse has one tooth missing in 3 different sections of the synchro and the 5th has 2 teeth missing in 3 sections. (Might be getting 5th and reverse mixed up). Well in my kit only one has the 2 teeth missing in the 3 sections which matches the 5th (or reverse) and the other smaller ring has all its teeth unlike the other old one. Is this and issue? Should I grind off the teeth to match the old ones or just throw them in there in place of the old ones. What's exactly do all these certain missing teeth affect?

rlong
12-31-2013, 03:59 AM
i put brass ones in a few years back and didnt like it second gear grinds , wish i would have used original type

BLOWN38
12-31-2013, 11:40 AM
I don't know about the missing teeth but I don't think you will need friction modifier with the brass blockers, so you can save your money there.

TbirdSCFan
12-31-2013, 02:10 PM
I would make them match. I believe the missing teeth makes it easier engage the gears.

TbirdSCFan
12-31-2013, 02:12 PM
I don't know about the missing teeth but I don't think you will need friction modifier with the brass blockers, so you can save your money there. I used to think so too; however after reading up a bit on what FM does, its not clear to me that it wouldn't help even with solid brass blockers.

ricardoa1
12-31-2013, 03:07 PM
I used to think modifier aided in friction, but I have been schooled that it actually caused more slip, the fiber material needs a a little slip so it does not chew itself up.

So we brass you want to use a trans fluid that will let the brass blockers grip more. Friction mod will just make things worse, or even not work at all since fric mod conditions organic material.

Think of it as conditioner for your hair.

TbirdSCFan
12-31-2013, 04:39 PM
Right in that FM allows more slip.. that is makes things more slippery.

I used to think that it conditioned the fiber part of the blockers too. But then I read that it bonds to the metal surface. Can't recall where I read that, but if its the case, then it would allow all metal/metal to be slippery-er too. At least that was what I took away from it. For a blocker to do its job, it can't be too slippery, since then it wouldn't grip/stop the grear's shaft. So there has to be a correct amount.

My advice is to fill up the case as needed, then drain out about 8 ounces, test drive and add FM 1 or 2 oz at a time and see if it eases the shift feel and stop when its good enough. Then top it off with regular synchromesh fluid.

rlong
01-03-2014, 08:58 PM
i never used anything but atf mercon or dex

Scott Long
01-06-2014, 08:18 PM
I had the brass synchros put in when I had my trans rebuilt back in 03. They are hard to get into 2nd gear. Notchy and it grinds if you force it. I wish I had used the fiber ones again. Hell they lasted over 150k miles the first time around.

Now Mike Puckett has some synchros for sale that I think are carbon fiber or Kevlar or something. If/when I rebuild mine again I'm going that route.

I have only driven my SC once since 2006 when I parked it, so my trans is still pretty fresh.

JeepsterSC
01-07-2014, 09:22 AM
I used to think modifier aided in friction, but I have been schooled that it actually caused more slip, the fiber material needs a a little slip so it does not chew itself up.

So we brass you want to use a trans fluid that will let the brass blockers grip more. Friction mod will just make things worse, or even not work at all since fric mod conditions organic material.

Think of it as conditioner for your hair.

If that's the case then why do people recommend putting multiple bottles of it in trac-lok differentials? I've had conversations with old hot-rodders who say the more of it you add the better. It always seemed kinda silly to me

ricardoa1
01-07-2014, 09:29 AM
You way of thinking is what got me confused. You only want what's needed, not more or less.

Its not glue, its a conditioner.

JeepsterSC
01-07-2014, 01:02 PM
you are confused. I wasn't endorsing the "no less than 2 bottles of friction modifier in your trac-lok" stance. I was just confused about why others endorse it I was like you, I had always thought that the purpose of friction modifier in TL diffs. was to prevent the TL from making noise when cornering by allowing some slip to take place. I had always thought that if you wanted the maximum bias for a drag race situation it might be better to leave out friction modifier all together. However I had separate conversations with 2 serious drag racers this last year were they said "no less than 2 bottles of friction modifier in your trac-lok". I could see why this might be desirable if you had a very tightly packed 4 friction setup, but in the second instance I was telling the guy that I couldn't run a 4 friction setup because the new friction disks from Ford are too thick.

Oh well. I didn't mean hijack anyone's thread. its just when you said what you said, it got me woundering

ricardoa1
01-07-2014, 01:20 PM
Super when you figure it out let us know.