Normal manual transmission noise?

Skip the OEM MTF and try some Redline MTL or Amsoil MTF
I just got the Honda fluid for the swap because I was in a hurry and had to go to the dealer to pick up other stuff anyways. I will probably get Amsoil the next time I change the fluid, which won't be too long. This trans had a little bit of glitter in it presumably from the badly worn input shaft bearing and I did my best to clean it out before I put it back together, but I'm going to change the fluid shortly to help flush out any remaining particles. If the fluid comes out reasonably clean I will probably refill with Amsoil. This trans only takes about 1.5 quarts of fluid, so the difference in cost isn't much and is well worth it IMO.
 
In a hurry, don't rule out the Valvoline MT fluid either
MT fluid isn't readily available in parts stores where I live, probably because there are barely any MT vehicles on the road here, so I plan to keep a few extra quarts of fluid on hand so I don't need to go looking for fluid when I need it next time.
 
I have a 2005 Civic LX Manual since new in the garage. Just under 200,000 miles now. After reading about the input shaft bearing issues I made sure to change the transmission fluid every 30-45K miles and always use Redline MTL. No noise from the input shaft bearing at idle and shifts smooth through all gears. MTL also cured the 1-2nd notchy shift it had since new.
 
It seems to be normal for manual transmissions to make some noise in neutral with the clutch engaged. At that point, lots of stuff in the gearbox is spinning due to mechanical connections and also oil drag.
 
It seems to be normal for manual transmissions to make some noise in neutral with the clutch engaged. At that point, lots of stuff in the gearbox is spinning due to mechanical connections and also oil drag.
Thanks, that does seem to be the case. I bet automatic transmissions make some noise too, but we don't notice it as much since there isn't a way to make it stop spinning like there is with a MT.
 
I should have been more careful in my wording above, saying the input shaft makes "no noise". You can hear it spinning at idle if you listen carefully; the slight whirring sound. By noise I mean that it is still sounding as new at 200K miles. No rattle, scrape, or grind noise that would indicate the bearing is failing.

The manual states that the transmission oil should be changed at 120K miles, or every 6 years. We know the oil will not hold up for nearly that long! I'm not sure if the failures are related to defect bearings or poor lubrication, but my sample of one is still working fine at 200K using Red Line MTL changed at 30-45K miles.
 
I should have been more careful in my wording above, saying the input shaft makes "no noise". You can hear it spinning at idle if you listen carefully; the slight whirring sound. By noise I mean that it is still sounding as new at 200K miles. No rattle, scrape, or grind noise that would indicate the bearing is failing.

The manual states that the transmission oil should be changed at 120K miles, or every 6 years. We know the oil will not hold up for nearly that long! I'm not sure if the failures are related to defect bearings or poor lubrication, but my sample of one is still working fine at 200K using Red Line MTL changed at 30-45K miles.
Thanks for letting us know, it's quite encouraging that your trans is still healthy after 200K miles. The input shaft seems to just be a matter of luck more than anything else. I have heard of people going 200K+ miles on the factory fill with no problems, but I have also heard of very early failures in well maintained transmissions. I'm sure the brand of fluid used is a factor to some extent, but using good fluid and changing it frequently unfortunately doesn't seem to be any guarantee that the bearing won't fail prematurely.

Something interesting I discovered from the research I did on what causes the input shaft bearing to fail is it doesn't seem like the K series transmissions used in the RSX, TSX, Civic SI, etc have nearly as much of a problem with the input shaft bearings as the D series transmissions used in the older Civics do. There are a few people who have reported problems, but not nearly as many. Whether that is due to some design difference or just because there are a lot less of those on the road I'm not sure. Perhaps those are built stronger to handle more hard driving/abuse since they were designed for more powerful and sporty cars that are expected to be driven harder.
 
After driving it for a while, I also noticed that I get a similar faint whining/whirring noise when downshifting when the clutch in. I really don't know if it makes that noise while I'm driving as my Flowmaster muffler is much louder than any noises the trans makes. Is this something I should be concerned about or is this normal for manual transmissions?

Also, I think my stiff polyurethane engine/trans mounts may be contributing to being able to hear the sounds of the transmission in the cabin. Up until about 2 weeks ago I just had the 2 side mounts and the rear mount as the front mount is different for the 5 speed, but I now have a front poly trans mount also and the whining/whirring noise it makes when idling in neutral seems to have gotten slightly louder now that I installed the front mount, but it's still barely noticeable. Also, I now notice that whirring/whining nose when downshifting and I didn't really notice it without the front mount. The noise doesn't bother me as long as the transmission is okay. Other than those faint whining/whirring noises it seems to be perfect, so hopefully there isn't anything wrong with it.
 
When my Mazda was still fairly new, I noticed the whirring sound was a little louder than expected. That noise slowly worsened until it was more of a roar by the time the odometer reached 340k miles. Replacing 3 transmission bearings then was the most expensive mechanical repair that car ever had, by far. After that, it stayed quieter than when new. I suspect the bearings were contaminated when new, or maybe excessively pre-loaded.
 
When my Mazda was still fairly new, I noticed the whirring sound was a little louder than expected. That noise slowly worsened until it was more of a roar by the time the odometer reached 340k miles. Replacing 3 transmission bearings then was the most expensive mechanical repair that car ever had, by far. After that, it stayed quieter than when new. I suspect the bearings were contaminated when new, or maybe excessively pre-loaded.
Good to know, thank you for sharing! I replaced the input shaft bearing before I installed the trans since that's a very common failure on these cars. I don't know the history or mileage of this trans since I pulled it out of a wrecked car at a junkyard, but it seemed to be in good condition inside with the exception of the trashed input shaft bearing.
 
The other thing I noticed is there have been a few times the trans didn't want to go into first gear when stopped. It feels like something binds sometimes. However, if I put it in neutral, let the clutch out, and push it back in it will go into gear no problem. All the gears consistently engage easily while rolling. Is this normal for a manual transmission or is it a sign of a problem? From my limited understanding of how a manual transmission works it seems like this could be normal if the synchronizer teeth don't line up when the transmission stops rotating, but I'm not sure since this is my first manual transmission. Thanks in advance!
 
On my 05 Civic 5spd,(200K miles) I have never encountered the problem you describe shifting into 1st while stopped. There are synchros in all forward gears, but not reverse, so this issue sometimes occurs for reverse only. What it doesn't like is down shifting into 1st when going much over 5mph. I don't downshift to 1st until almost or completely stopped.( 1st is geared so low anyway, hardly ever a reason to use it unless starting from a stop)
Maybe your synchro in 1st is compromised a bit....
 
On my 05 Civic 5spd,(200K miles) I have never encountered the problem you describe shifting into 1st while stopped. There are synchros in all forward gears, but not reverse, so this issue sometimes occurs for reverse only. What it doesn't like is down shifting into 1st when going much over 5mph. I don't downshift to 1st until almost or completely stopped.( 1st is geared so low anyway, hardly ever a reason to use it unless starting from a stop)
Maybe your synchro in 1st is compromised a bit....
Thanks for the info. Since my swap was from a junkyard, I don't know how this trans was treated or how many miles are on it but it looked alright inside with the exception of the input shaft bearing. I don't think my issue is that bad since it only happened a few times and it shifts fine otherwise.

Mine doesn't like downshifting to 1st while rolling either, which I do not like. I may be able to get around that by double clutching though, I haven't tried yet. Hopefully getting the Amsoil Syncromesh fluid helps a bit too, I will report back when I try it.
 
I have on 05 ex mt with 248k miles. My transmission makes some shhhhhhh noise with the clutch out in neutral and while coasting in gear at higher rpms. It’s been like this since I got it 50k miles ago and hasn’t gotten worse. I use Pennzoil mtl from the parts store and change it every few oil changes. I also tilt the car when I fill the trans to get a few more ounces in. You can also add fluid through the tiny vent pipe on the top.
 
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