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Anyone ever "fix" a scratchy synchro with fluids?

Old Nov 20, 2012 | 10:42 PM
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Default Anyone ever "fix" a scratchy synchro with fluids?

I have a 6-speed running MTG but it's a huge POS crunch-box. 3rd gear does not like to downshift. Can I add some GM friction mod or AMSoil slip lock and get any improvement?
Old Nov 21, 2012 | 09:43 AM
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Synchros need friction to function properly. Adding friction modifiers (ie slipperiness) will make them worse.
Old Nov 21, 2012 | 10:49 AM
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Originally Posted by y8s
Synchros need friction to function properly. Adding friction modifiers (ie slipperiness) will make them worse.
I never knew what FMs did, never researched it. I thought they made things more slickery. I guess I can over-fill and see what that does.

Never, ever buy a transmission from an auto-x'er, even if he says he only drove it a couple times.
Old Nov 21, 2012 | 11:07 AM
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wait didn't you yell at a n00b for suggesting the same thing?

LOLOL

oh the ironing
Old Nov 21, 2012 | 11:11 AM
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Originally Posted by 18psi
wait didn't you yell at a n00b for suggesting the same thing?

LOLOL

oh the ironing
Never. Again, I don't understand how the slip-lock works so I'm not going to troll anyone over it.
Old Nov 21, 2012 | 01:32 PM
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Originally Posted by hustler
I don't understand how the slip-lock works so I'm not going to troll anyone over it.
Friction is used to accelerate/decelerate the input shaft to make the next gear slide in smoothly. Blipping during downshifts makes this process faster.

At least that's my understanding and I'm content with that level of detail (ignorance is bliss ).
Old Nov 21, 2012 | 01:34 PM
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What fluid are you running in the trans?
Old Nov 21, 2012 | 02:00 PM
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Originally Posted by NiklasFalk
Friction is used to accelerate/decelerate the input shaft to make the next gear slide in smoothly. Blipping during downshifts makes this process faster.

At least that's my understanding and I'm content with that level of detail (ignorance is bliss ).
Oh goody, answers to questions I didn't ask. Tell me more.
Old Nov 21, 2012 | 02:01 PM
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Originally Posted by Fireindc
What fluid are you running in the trans?
Half AMSoil MTG, half pterodactyl ejaculate.
Old Nov 21, 2012 | 02:05 PM
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friction modifier is used to reduce friction between parts.

synchros NEED FRICTION to work.

gohead and add it and complain more?
Old Nov 21, 2012 | 02:08 PM
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Originally Posted by y8s
friction modifier is used to reduce friction between parts.

synchros NEED FRICTION to work.

gohead and add it and complain more?
I was on board with slip-lock reducing friction from post #2 of this thread.
Old Nov 21, 2012 | 02:50 PM
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this stuff? AMSOIL - Synthetic Manual Transmission and Transaxle Gear Lube 75W-90 (MTG)

Seems like it would work well, although I'm using this ford motorcraft fluid and noticed a huge difference from whatever the fck was in there previously.

Motorcraft MTX-75 IB5 transmission fluid XT-M5-QS

Although since that Amsoil stuff is GL4 fluid it should be good from what i've read. I LOVE amsoil and it's all i run in my Buell.
Old Nov 21, 2012 | 05:01 PM
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The Motorcrap posted above was a step up from my redline, it noticeably improved shifting.
If not, I have a synchro or two if yours are out of spec I could mail you.
Old Nov 21, 2012 | 06:22 PM
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This thread is perfect timing. my new to me, sat on a garage floor for a year or two 80,000 km 6 speed shifting was/is horrendous as well.

I might try the motorcraft if we can get it here BUT have noticed in the past week as i use the car more, the gearbox is improving. Perhaps sitting around wasn't the greatest and using it is wearing any rust or whatever off.....

I race national MX here in NZ, the Motul "Pro" gearbox oil is shithouse. Jumps out of gear, won't go in to gear etc....(life threatening on a MX track!)"Downgrade" to the bog standard Motul transmission oil (1/2 price) and shifts are perfect.

I came to the conclusion the "Pro" **** was too slippery and the synchros etc were not coping....told my friends who were haivng the same problem and they all ended up with the same conclusion.

Who knew, oil can be too slippery....!
Old Nov 21, 2012 | 08:27 PM
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You may find your self diving into the art of tranny rebuilds. Put on your happy face.
Old Nov 21, 2012 | 09:05 PM
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STFU about the Motorcraft **** gear lube. This is not that thread, go away.
Old Nov 21, 2012 | 09:07 PM
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Originally Posted by mx5-kiwi
This thread is perfect timing. my new to me, sat on a garage floor for a year or two 80,000 km 6 speed shifting was/is horrendous as well.

I might try the motorcraft if we can get it here BUT have noticed in the past week as i use the car more, the gearbox is improving. Perhaps sitting around wasn't the greatest and using it is wearing any rust or whatever off.....

I race national MX here in NZ, the Motul "Pro" gearbox oil is shithouse. Jumps out of gear, won't go in to gear etc....(life threatening on a MX track!)"Downgrade" to the bog standard Motul transmission oil (1/2 price) and shifts are perfect.

I came to the conclusion the "Pro" **** was too slippery and the synchros etc were not coping....told my friends who were haivng the same problem and they all ended up with the same conclusion.

Who knew, oil can be too slippery....!
You have a GL5 lube in when a GL4 is required, no wonder it shifts like ****. the AMSoil MTG is for extreme use, Motorcraft and Synchromesh for dialy driving.
Old Nov 21, 2012 | 09:07 PM
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Originally Posted by chicksdigmiatas
The Motorcrap posted above was a step up from my redline, it noticeably improved shifting.
If not, I have a synchro or two if yours are out of spec I could mail you.
Thanks but I'll just dump this trans and get another...from my garage.
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Old Nov 21, 2012 | 09:08 PM
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I just changed the shift boot from the old vinyl one to a leather boot. Do you think that will increase my homosexual lust?
Old Nov 21, 2012 | 09:33 PM
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I have been running Royal purple for the last 14k miles, id say its pretty good. Then again my **** only has 34k miles.

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