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5th gear synchro

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Old 12-04-02, 07:57 PM
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5th gear synchro

Got into the tranny and the 5th gear synchro out with no problem. Thought someone might be interested in what a bad one looks like. It was broken in two places but only one break was all the way through so the piece didn't drop into the tranny. When I got it out I pulled on it a liitle bit and it broke in half. The moral being if you hear it grinding into 5th DON'T force it. If the ring broke in half I would have had a lot more damage.
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Old 12-04-02, 08:06 PM
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Could you post a picture of your Trans. I am in the process of changing out the clutch and would like to do the 5th gear synchro while in the vicinity.

Thanx
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Old 12-04-02, 08:39 PM
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See if these help. #1


Last edited by dgeesaman; 10-21-07 at 07:08 AM.
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Old 12-04-02, 08:41 PM
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#2



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Old 12-04-02, 08:45 PM
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#3



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Old 12-04-02, 08:45 PM
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#3

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Old 12-04-02, 08:49 PM
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Not sure why that last one posted twice?!
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Old 12-04-02, 08:55 PM
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how about a shot of your 5th/ reverse hub set? i bet the teeth are shot on that too

mike
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Old 12-04-02, 09:00 PM
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I'll have to look closer but do you mean the ones that are out of the tranny in picture #2 or the ones still on the main shaft?

Jim
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Old 12-04-02, 09:36 PM
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its still on the mainshaft, its the thing the synchro fits in

mike
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Old 12-04-02, 10:24 PM
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Thanks for the pics and info!


This thread is a keeper.
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Old 12-04-02, 10:43 PM
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hey.......

When I first got my 7 the 5th gear synchro was busted also. If you don't mind me asking, how did it happen? What did you do?

Regards, Matt
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Old 12-05-02, 07:29 AM
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Missed the 2-3 shift at the strip in Epping NH and hit 5th but it didn't go in. It only took one time and it wouldn't go in to 5th again. I updated the shift select spindle with the synchro repair. The new version is supposed to have a stiifer spring.

Thanks j9fd3s I'm definitely going to go into the tranny further with that advice.

Jim
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Old 12-05-02, 07:36 AM
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Yeah my 5th is shot too. Gotta double clutch that **** to avoid grinding. It sux.
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Old 12-05-02, 07:53 AM
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Excellent pics. Thanks.
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Old 12-05-02, 07:57 AM
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I get grinding when i shift from 3->5. Is this a 5th gear synchro problem?
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Old 12-05-02, 08:51 AM
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how difficult was the whole task of replacing it? i think mine needs replacing and i want to do it myself.
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Old 12-05-02, 10:08 AM
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You might want to consider changing your 5th gear ratio while you're in there to make it not suck so hard.

I'm doing mine right now and I'm putting in a .806:1 rather than the stock .719:1

This will give me a more useful 5th.

Brian
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Old 12-05-02, 10:39 AM
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yeah mine is shot too I think. For me to get into 5th though I just wait a sec. or two and then shift 4->5 and it doesn't grind then. So maybe it's not hurt too bad.
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Old 12-05-02, 10:48 AM
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Wargasm,
Is that a stock gear from some other tranny or did you have one made?

shmaLbus,
Not difficult and really no special tools needed that you can't make yourself to get at the synchro ring.


Jim
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Old 12-05-02, 10:59 AM
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Is this problem with all Fds of just specific(sp?) years. Not to sound stupid, but how would you double clutch. are you taking about like the big rigs, where you got to press the clutch twice, or is this some racing terminology
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Old 12-05-02, 12:01 PM
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Very helpful pics! I have to replace my 5th gear sync as well. Ill have to save those.
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Old 12-05-02, 12:04 PM
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Originally posted by namasan
I get grinding when i shift from 3->5. Is this a 5th gear synchro problem?
FYI, there should be a 4 after 3, but before 5. That could explain the grinding
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Old 12-05-02, 12:58 PM
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Originally posted by Turbo_F1
Is this problem with all Fds of just specific(sp?) years. Not to sound stupid, but how would you double clutch. are you taking about like the big rigs, where you got to press the clutch twice, or is this some racing terminology
Double clutch in the way he sued it is where he presses the clutch in once puts it in nuetral pushes the clutch in again and then puts it into 5th. Maybe not in this exact way but that's the basics and it happens faster than it sounds.
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Old 12-05-02, 01:15 PM
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Originally posted by SanJoRX7


FYI, there should be a 4 after 3, but before 5. That could explain the grinding
yes, the taller 5th gear of the fd means that the synchro has to slow down the gear even faster (than say a t2), conbine this with a misshift, and you exceed the strength of the synchro. putting a lower (or lighter) 5th gear, would improve the "problem" but the broken 5th is common to every 5 speed r box from 1970 to 2002.

mike
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