MUSTANGBRKR02

iTrader: (91)

Is it necessary to replace these when rebuilding a tranny? Mine look perfectly fine and fit nice and tight. But I do have to replace the keys with billet ones. Trying to rebuild it cheap not be cheap though.

85MikeTPI

iTrader: (9)

What are you calling synchros? Synchros are assemblies that include the hub/springs/keys/slider and work closely with the blocker(friction) rings to engage the gears.

You can check if you need new carbon-fiber blocker rings with some machinist dye, but on high-milage units it's probably best just to replace them all. If your T56 is older and has paper-lined blockers, you'll want to replace them.

If the slider teeth are in good shape, there's no need to replace them. Mark them in alignment with the hub and disassembly to install the billet keys and new springs, then reassemble in the same alignment. Use a transmission grease when you reassemble that will keep things in place, lubricate during initial break-in, and dissolve out in ATF during break-in.

MUSTANGBRKR02

iTrader: (91)

Thanks for the reply. I was referring to the hub and slider. The ones I have look great except on the 3/4 I had a broke key. Everything in the tranny looks good except the broke key. All normal wear.

the_merv

iTrader: (88)

The Tick Stage II is a good upgrade Kit.

85MikeTPI

iTrader: (9)

I think that's the point of the post/question. The "kits" include the synchro assemblies, if you need them or not.

MUSTANGBRKR02

iTrader: (91)

Yes that is the point. Just don't want to spend money if it isn't needed.

the_merv

iTrader: (88)

I would replace them..why waste new parts..? Save the used ones for spares.

I have a full set of CF Synchro's as extra that I pulled out of a friends Tranny..someone attempted a rebuild, I did it the right way.

MUSTANGBRKR02

iTrader: (91)

I wouldn't waste them. I just wouldn't buy them.

LS123

iTrader: (11)

Replace the synchro if you see wear on the engagement teeth.

Good synchro.



Bad synchro.



Also, if the synchro is worn that means the corresponding gears engagement teeth is worn too!

MUSTANGBRKR02

iTrader: (91)

Thanks LS123. My syncro gears look just like the top ones. Appreciate the help.