Synchro issue?
 

So I've only had the brz for 3 weeks and I noticed very early on maybe 3-4 days in....that when I shift at high rpms like 6-7 that the shifter makes a nice like the synchro is out....like a sort of metallic chatter....but at lower rpms its fine....am I shifting it wrongly? The only other stick I drove was a 5 speed 95 neon.....at it had a legitimately broken synchro in 5th gear...so I had learned early to double clutch the car into 5th, so I know this distinct feeling...but I also have no experience with 6 speeds...is it possible that I have to wait a little bit before shifting?

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I got a brand new transmission from Subaru when I took my car in. They claimed 'this is normal for this car" until they actually drove it. But the issue was from. 3rd to 4th.

It happens in any gear going from 3rd to fourth and up, only up shifting.

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Is there both an audible grind and physical grinding feedback through the shifter when shifting at high RPM, or only one of the two? As long as you are fully pressing the clutch pedal to the floor before engaging the next gear, it shouldn’t grind. If you are doing this and it grinds... that’s what your warranty is for (assuming you aren’t past 5yrs/60k) , let the dealership sort it out.

Synchros are notoriously bad in these cars :/

I've gotten warranty replaced on the trans around 25k miles bc the 5th gear would almost always grind after a while.
I'm having some high rpm downshifting problems now. I'm hoping the new trans fluid just needs some miles and seat time.

Hence these existing - https://www.verus-engineering.com/pr...on-synchro-kit

Hello 8luedragon and welcome to the group of people who are having difficulties with shifting this transmission...:clap:

I figure in your case the difficulty can be attributed to about 50% transmission and 50% driver inexperience (with this transmission).

This transmission is not the easiest transmission to shift. It doesn't like to work smoothly when it is cold. It is fairly precise in its workings, which causes it to be somewhat finicky.

Now, after the transmission warms up it works better. It also works better with age (> 10 years old).

Now, about the driver part. I suggest you be patient with it when it's cold, maybe within the first 2-4 miles.

Smooth shifting is all about timing. The timing of the clutch use, application of the gas and movement of the shift lever. Also, timing as far as letting the transmission prepare to move into the next gear.

Now, I can't tell you how to do this. With enough "practice" you will figure it out.

Those of us that were raised on manual transmissions, some without synchronizers, we learned the technique at an early age and find this transmission easy to shift.

To demonstrate on how you know when you have the shifting down, I offer you the:

The shifting challenge

To understand the "timing" of shifting a MT, I suggest you try this technique.

With the transmission warmed up, learn to shift UP the gears WITHOUT using the clutch OR blipping the throttle.

Drive your car a couple miles out to a quiet country road, without a co-pilot, so you can become one with your transmission.

Yes, use the clutch to put it into first gear, after the car gets going, let off the gas and slip the car into second gear (without using the clutch or hitting the throttle). Do the same from 2nd to 3rd and 3rd to 4th.

Once you "learn" the timing, by getting it "right", you should be able to shift up through the gears without feeling (or hearing) the gears mesh.

After you have mastered this technique, shifting using the clutch, is a snap.

If old humfrz can consistently do this in his FR-S, I know you can in your car.


humfrz

You should leave a note - any damage inflicted upon your transmission is fully at your own risk and humfrz holds no responsibility for any damages should any occur.
:popcorn:

Good thought.

:D


humfrz

To answer your questions...it does make a audible sound and gives feedback through the shifter....I have shifted trannies clutchless before...just not on this car...in all instances of high rpms operation I always warm the car up beforehand...but thanks for the feedback...good info here...although I still can't say for certain if it's me or the tranny.

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Why do you figure it has to be one OR the other?

How about sharing the "problem" - :)


humfrz

I did share the problem...the synchro not doing its job at high rpms.....and I did some testing...if I accelerate in 3rd up to 6k and then stand on the clutch for a second and then shift ...it still acts as if the synchro is out. Also I dont just assume it's one or the other.... try to rule out as many options as possible. Shifting the same way except at lower rpms is perfectly fine and smooth but at high rpms it still acts up. Which tells me it's less me and more car.....so I'll do a few more tests till I'm positive and then have a service tech take a look.

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You ever figured out what happened? Mine is only at 3-4 on upshifts at close to redline or when shifting quickly but the clutch pedal is funny depressed. I had the car for just about a year and the MTF changed out at first chance I noticed it (1 month).