Synchromesh or Friction Modified Synchromesh?
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From: Maryland
Synchromesh or Friction Modified Synchromesh?
So, as the title of this thread suggests, which Synchromesh; I see the following two on Amazon:
- ACDelco 10-4006 Synchromesh Manual Trans Fluid
- ACDelco 10-4014 Friction Modified Synchromesh Manual Trans Fluid
Senior Moderator
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From: SoCal, CA
that's some good juice! I did my tranny fluid 2 months ago and it basically cures that 3rd gear notchiness. Before, I cringed everytime I had to shift to 3rd =[. It was awful lol. Now, I don't even think about it anymore. IMO, this is the first maintenance/repair that any MT TL owner should do, aside from anything safety-wise.
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Thread Starter
Joined: Jan 2017
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From: Maryland
Yeah, I remember breaking the fill bolt (17mm if I remember correctly) loose on my 2001 V6 Accord; I was surprised how much bend I got in my breaker bar before the damn thing finally popped.
Team Owner
Joined: Jun 2014
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From: In an igloo
why would it be difficult to open? I opened it with what I'd consider normal effort. As long as the battery tray is removed, you get full unobstructed access- throw the socket wrench on with an extension and turn. 
edit: maybe I got lucky?
Team Owner
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From: In an igloo
I find the GMSMFM an interesting fluid... I've done two fluid drain and fills on the TL in the last 3 or 4 years and I always notice the same feeling (even noticed it on some other Hondas I had)-
Just after swapping the fluid for fresh stuff, I feel the shifter feels a bit notchy.... but after about a couple weeks of driving, it gets nice and smooth. First time I did it (on a civic, about 8 years ago), I thought I was wearing down my synchros or something, until the tranny felt smooth to shift. I was nervous, but I wasn't getting any shifting grinds, so I figured I'd leave it as is until any issues started coming up (hey, I was poor back then, and that GMSMFM is expensive
)
Eventually, after draining the fluid, there were no metal flakes in it. No issues. No problems I could see. Filled it back up with GMSMFM and again, same feeling... a bit notchy for the first few weeks, and eventually gets butter smooth. No grinds during the notchy period, just a slightly "off" feeling shift. I wonder if some hot/cold cycles cause something to change with the fluid. It's not even a very noticeable notchyness... Wifey never noticed it... but then again, I feel I pay attention to a lot of stuff she wouldn't even bat an eye at.
Either way, I've put countless miles on cars/transmissions using GMSMFM, and I've never had an issue with it. That stuff is magic. I'm sure of it. I swear by that stuff and would never hesitate to put it in another Honda manual transmission... then again, I never did hesitate as I don't think I've ever heard of anyone having issues using it. Ever. In like 10 years. Except for the suckers who put in the non-friction modified stuff by accident... I've heard the Non-FM stuff is garbage.
Another thing of note- the smell of that fluid- wowza. When I cracked open the drain plug and had the fluid draining, I remember being like "man, this stuff really was due for a change... it smells funky!" and then I opened a new bottle... it smelled twice as strong.
I'm certain it's likely the magic that GM puts into the bottle. It has to be.
Just after swapping the fluid for fresh stuff, I feel the shifter feels a bit notchy.... but after about a couple weeks of driving, it gets nice and smooth. First time I did it (on a civic, about 8 years ago), I thought I was wearing down my synchros or something, until the tranny felt smooth to shift. I was nervous, but I wasn't getting any shifting grinds, so I figured I'd leave it as is until any issues started coming up (hey, I was poor back then, and that GMSMFM is expensive
)Eventually, after draining the fluid, there were no metal flakes in it. No issues. No problems I could see. Filled it back up with GMSMFM and again, same feeling... a bit notchy for the first few weeks, and eventually gets butter smooth. No grinds during the notchy period, just a slightly "off" feeling shift. I wonder if some hot/cold cycles cause something to change with the fluid. It's not even a very noticeable notchyness... Wifey never noticed it... but then again, I feel I pay attention to a lot of stuff she wouldn't even bat an eye at.
Either way, I've put countless miles on cars/transmissions using GMSMFM, and I've never had an issue with it. That stuff is magic. I'm sure of it. I swear by that stuff and would never hesitate to put it in another Honda manual transmission... then again, I never did hesitate as I don't think I've ever heard of anyone having issues using it. Ever. In like 10 years. Except for the suckers who put in the non-friction modified stuff by accident... I've heard the Non-FM stuff is garbage.
Another thing of note- the smell of that fluid- wowza. When I cracked open the drain plug and had the fluid draining, I remember being like "man, this stuff really was due for a change... it smells funky!" and then I opened a new bottle... it smelled twice as strong.
I'm certain it's likely the magic that GM puts into the bottle. It has to be.
Thread Starter
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From: Maryland
The GMSMFM smell thing is just like the computers and smoke thing; they put the smell/smoke into the product in the factory, however, if the smell/smoke ever comes out, the product will fail.
The DVD-A Script Guy
Joined: Apr 2005
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From: CT
I believe it's the increased diameter/surface area of the fill plug's flange causing it to be more difficult than something like the oil drain. I've definitely found it a pain to crack free. It's probably also magnified by the fact I need to use a long extension to get down there. So when it does crack free there's also the windup of the extension releasing as well. It's about the same size as the fill plug in the rear diff of our CR-V but I can get the driver right on that one without any extension and it's much easier. Still cracks free with a pretty good click but nowhere near as hard to crack or "violent" when it does crack free.