Episodically stuck shifter (not clutch pedal) on downshifting to 3rd/2nd

[neuronbob]

Shifter is occasionally stuck momentarily ONLY when downshifting, usually to 3rd or 2nd, never the other gears. Been doing it since I purchased the car. I have to double clutch at times to complete the shift. I've been driving stick for 30 years and I know the clutch pedal is fully engaged whenever I shift. Worse when the transmission is cold initially, better after driving a while.




Clutch pedal is not stuck at all, never has trouble moving, and is absolutely not slipping--problem's not there.




I had the NSX tech at my local dealer change the master and slave cylinders, and do a tranny fluid change before NSXPO a few months ago and that improved, but has not resolved the behavior.




My current plan is to change from the HondAcura transmission fluid to GM Synchromesh--I used this in my S2000 when I had it, and of course in my 6MT CTS-V (duh) with fantastic results. However, if possible, I'd like to address the underlying issue. Is this the synchros? Do they need replaced? or is this something else?




I've searched on Prime and found threads about people having trouble upshifting, very little on difficulty downshifting. Thanks for any advice, or if I'm missing any obvious threads, do link away. It's more annoying than anything else but if I can address it, I'd like to try.

 

[neuronbob]

One additional question: What are typical labor hours for replacement of the synchros?

 

[RSO 34]

I texted Larry B to let him know about this thread.

 

[Larry Bastanza]

I would try the GM Syncromesh. Does it ever grind, or just refuse to move into the gate?

 

[neuronbob]

Thanks, guys!

The only grind I get is when UPshifting really quickly into 5th, and that is rare. The shifter is stuck only after DOWNshifting, and the stick is in the 2nd or 3rd gear position.

I've already spoken with my dealer to arrange a GM Syncromesh fill, so we'll see how that works.

 

[furinax]

I'm interested in this too. Mine gets stuck in gear a couple times at most every gear and takes plenty of muscle to come out. It also grinds every once in a while, but those are quick shifts and I may just be doing it wrong. I have a spare tranny and was thinking of doing a rebuild and swap, but then again that's $3k that I am not sure I can spare right now. A trans fluid swap made shifting smoother but did not fix the stuck gears problem. I am still not sure if it is temp related or not.

 

[neuronbob]

Wow. Sounds like you are in worse shape than me. In my case, I am already seeking a set of new 6-speed synchros in case the GM Synchromesh switch doesn't work. Since my problem is intermittent, it'll be an end-of-season project.

Anyone know an approximate number of hours that would be charged by a shop to drop the tranny and replace the synchros? I'd like to be able to plan/budget appropriately.

 

[tdiggity]

Science of speed quoted 8 hours to drop, reinstall, and do initial investigation for an issue I had with reverse gear.


Sent from my iPhone using Tapatalk

 

[neuronbob]

I reposted a new thread about my intermittent 5th gear grind and in doing so, realized I forgot to update this thread. I switched to GM Synchromesh in September, right before NSXPO. It nearly eliminated the stuck gear issue. Thanks for the suggestion, [MENTION=3729]Larry Bastanza[/MENTION] !

 

[dwe8922]

I wonder if it would be worth trying the fluid change to GM in my '91. It occasionally has difficulty coming out of gear on downshifts. It seems to happen on several gears. I could pull harder and it would come out, but I give a slight tug, release, and then pull again and it comes out smoothly. I am getting ready to basically rebuild my transmission with short gears and 4.23 soon, so it might be best to wait and see how it all looks on inspection....