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Does anyone else notice a transmission grind upshifting from 1st to 2nd or 2nd to 3rd? Even with the clutch fully depressed, it seems the syncros aren't keeping up.

Also, noticed it more unless I backed off the throttle a moment before depressing the clutch. Makes me wonder if the Ktuner rev hang delete will correct this or if just replace with the K-tuned clutch master/slave combo.
 

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Does anyone else notice a transmission grind upshifting from 1st to 2nd or 2nd to 3rd? Even with the clutch fully depressed, it seems the syncros aren't keeping up.

Also, noticed it more unless I backed off the throttle a moment before depressing the clutch. Makes me wonder if the Ktuner rev hang delete will correct this or if just replace with the K-tuned clutch master/slave combo.
You are probably right. The synchros are not keeping up. I’ve not driven a 2018 yet, but my 2002 RSX-S, 2007 V6-6MT and current V6-6MT would all snick with quick, low-rpm shifts. (At higher rpm it was better.) I even had the 3rd gear synchro in my 2007 replaced under warranty and it still snicked a little. High quality MT fluid (like AC Delco Semi-Synthetic with friction modifiers) can help a little. It’s a Honda thing. At low rpm, you just have to shift slower.
 

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Corvalis TTX
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Honda and Acura MTs have been doing this for over a decade now and Honda hasn't addressed this? It's very telling when a fluid from a competitor can alleviate this issue (assuming that the issue in the 2.0 MT is the same as Hondas of days gone by).
 

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I have not experienced what I would call a GRIND yet...like in that video of the Type R shift...or you get if you miss a shift (not all the way in gear, or release the clutch too early etc)...

but I will say that I have experienced what was described above as "crunchy" shifts...we're probably describing the exact same thing, I just wouldn't use grind as the word to describe it...where it didn't slide into gear buttery smooth...there wasn't much additional resistance, meaning I didn't feel like I had to force it into gear, but it just wasn't as smooth...it DOES feel like it could be a syncro not matching up

Also something I've noticed, and this could be my lack of experience with many different auto makers, and might just be normal on these cars but I feel like the gear lever is a little "sloppy"(?) When the car is IN GEAR...

The best comparison I can make is my Mustang, which I've owned for 16+ years now...but when that car is in gear the stick itself is rock solid, does not budge one millimeter until the clutch is depressed and you take it out of gear...

The Accord on the other hand definitely has some "play" side to side while in gear...it doesn't feel like it's going to pop out of gear or anything like that, it doesn't have any play back to front...but it's just a little odd to me...
 

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Corvalis TTX
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I have not experienced what I would call a GRIND yet...like in that video of the Type R shift...or you get if you miss a shift (not all the way in gear, or release the clutch too early etc)...

but I will say that I have experienced what was described above as "crunchy" shifts...we're probably describing the exact same thing, I just wouldn't use grind as the word to describe it...where it didn't slide into gear buttery smooth...there wasn't much additional resistance, meaning I didn't feel like I had to force it into gear, but it just wasn't as smooth...it DOES feel like it could be a syncro not matching up

Also something I've noticed, and this could be my lack of experience with many different auto makers, and might just be normal on these cars but I feel like the gear lever is a little "sloppy"(?) When the car is IN GEAR...

The best comparison I can make is my Mustang, which I've owned for 16+ years now...but when that car is in gear the stick itself is rock solid, does not budge one millimeter until the clutch is depressed and you take it out of gear...

The Accord on the other hand definitely has some "play" side to side while in gear...it doesn't feel like it's going to pop out of gear or anything like that, it doesn't have any play back to front...but it's just a little odd to me...
The difference is that the shifter in your Mustang goes directly into the transmission. In a FWD car there are either long linkages or cables going from the shifter to the trans. Some FWD cars are better than others, though. VW/Audi have long had better and more positive manual shifters than Honda/Acura.
 

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The difference is that the shifter in your Mustang goes directly into the transmission. In a FWD car there are either long linkages or cables going from the shifter to the trans. Some FWD cars are better than others, though. VW/Audi have long had better and more positive manual shifters than Honda/Acura.
Ahhh...ya know, that's not even something that crossed my mind.
 

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The difference is that the shifter in your Mustang goes directly into the transmission. In a FWD car there are either long linkages or cables going from the shifter to the trans. Some FWD cars are better than others, though. VW/Audi have long had better and more positive manual shifters than Honda/Acura.
I beg to differ on the VW/Audi point. It really comes down to shift bushings, the linkage setup, and the counterweight on the trans. My '03 AV6 6MT and '11 TL SH-AWD 6MT had far more positive engagement than any VAG product I've sampled (many of them). I could see your point on a base Civic or Accord, but on the 'sportier' models it's a different story. This Accord isn't the greatest in terms of shift feel but it still feels better than my friend's '15 GTI 6MT.
 

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GM Syncromesh Friction Modified transmission fluid has been a cure for trans grind in Honda transmissions for 20+ years. May work in this one too.
I tried this years ago, as probably every S2000 owner, and was pleased with the feel but it didn't last long enough for me and went back to MTF. What I feel in the Accord I believe is bushing/linkage related in part. I hope 70 bucks and 45 min of my time in the garage will improve the feel.

Edit: I just watched all the video. The part about the 3rd gear popping out is interesting. In the AP1 S2K like mine, it's 4th gear that pops out. Started that shortly before warranty ran out but hard to duplicate at that time. Later Honda changed from brass to carbon fiber syncro in AP2. My Odyssey also eats through ATF on a regular basis or else you get torque converter slip. Fingers crossed on this model.
 

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GM Syncromesh Friction Modified transmission fluid has been a cure for trans grind in Honda transmissions for 20+ years. May work in this one too.
I tried this years ago, as probably every S2000 owner, and was pleased with the feel but it didn't last long enough for me and went back to MTF. What I feel in the Accord I believe is bushing/linkage related in part. I hope 70 bucks and 45 min of my time in the garage will improve the feel.
Let us know what you think of the bushings
 

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The difference is that the shifter in your Mustang goes directly into the transmission. In a FWD car there are either long linkages or cables going from the shifter to the trans. Some FWD cars are better than others, though. VW/Audi have long had better and more positive manual shifters than Honda/Acura.
I still have a '84 Porsche 944 that is now parked for future repairs (A collection of random VW/Audi parts). That gear shift is so bad (at least in mine) that the play in gear is almost as much as when it's in neutral.

I see you also had an MGB. We had multiple in the family and is what I first learned to drive in. A 1972 MGB-GT and a '69 Midget. People who don't love constantly fixing their car need not apply.
 

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I have the hybrid racing bushings installed and it does give a much more solid feel to the shifter. I also am running hondata stage 2 tune which gets rid of rev hang, has made the a huge difference in how the car shifts.
 

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I still have a '84 Porsche 944 that is now parked for future repairs (A collection of random VW/Audi parts). That gear shift is so bad (at least in mine) that the play in gear is almost as much as when it's in neutral.

I see you also had an MGB. We had multiple in the family and is what I first learned to drive in. A 1972 MGB-GT and a '69 Midget. People who don't love constantly fixing their car need not apply.
My MGB was a summer only car (the heater was simply not up to Canadian winters even with an insulated hard top). It certainly needed constant attention to keep it running.

I remember driving the 944 when it first came out and I honestly don't recall the quality of the shifting. 30+ years is a long time for a memory to fade (and for a linkage to develop play :))
 

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I was afraid this would happen. After the fiasco with the CTR grinding gears it seems that the Accord isn't immune either. Glad I didn't get the manual. I am sure Honda will send out a TSB to address this.
 

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This photo below is from @Graycar’s video. Can you believe how chewed up that synchro is? I’m sure this is a worst case example, but still.

As mentioned earlier, I had my 3rd gear synchro replaced in my 2007 6-6. If I may add something from my experience, when evaluating my car, the first tech to test drive it could barely drive a stick shift. I’m sure he could follow a repair manual and fix a MT, but he had no idea how a MT should feel or sound. In his opinion my 2007 was fine. When I brought my car back to the same dealership the second time, I specifically asked for a Master Tech with MT experience to drive it. When he drove it, he instantly felt the snick and gave the green light for the repair.

During the test drive the Master Tech explained what wasn’t happening correctly. The synchro’s job is to connect the input and output shaft. (Conceptually it is input shaft, gear, output shaft.) When the MT is in gear, the input shaft spins at engine rpm and the output shaft spins at “the wheel's” rpm. (The differential is a function of the gear ratio between them.) If you leave 2nd gear at 3,000 rpm and enter 3rd gear at 2,000 rpm, the input shaft must instantly drop from 3,000 rpm to 2,000 rpm. (2,000 rpm is the output shaft speed.) The change in input shaft speed happens during split second you slide the shift lever from one gear to the next gear. (This has nothing to do with the clutch or slave cylinder.) As you move the stick shift lever past neutral and into the next gear, the synchro’s teeth and dog collar’s teeth must match speed and align before they can fit together. The teeth can only fit together when an opening allows them to fit together.

The tech described that moment in time when the teeth align as a window. This window opens and closes very rapidly as the two rings spin past each other. If you push the shift lever at the exact moment a window is open, the gears fit together and the two shafts are connected. If you push the lever and the window is closed, you get a snick or even a grind as you force the two gears together. At low rpm, there might be 10 windows per second available for the teeth to align. But at higher rpm there might by 30 windows per second. The likelihood of a “fast shift” finding an open window at high rpm is 3X as great as finding an open window at low rpm. So at lower rpm you need to move the shift lever slower to “find” that open window and not jam the synchro into the dog collar. But at higher rpm, there are many more windows per second available for the teeth to align, which permits a faster movement of the shift lever.

The tech stated that to some degree, all MTs have the same timing issues. But for some reason, Honda is much worse. Perhaps the input shaft keeps spinning at a higher speed for a longer time. (If the clutch is depressed and the shift lever is in the neutral position, that input shaft is free floating and will slow down due to internal friction.) Compared to other cars, Honda's input shaft may not slow down quickly inside the MT when the clutch is depressed and the shift lever is in neutral. The faster the input shaft spins relative to the output shaft, the more force it puts on the synchro as the synchro matches the speed.

Bottom line according to the tech, if you get the snick move the shift lever slower. It may give the input shaft a split second more time to decrease its rpm (while the shift lever passes through neutral) and will also allow more time for the teeth to find an open window, align and connect.
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