My 2000 Accord with a manual transmission is have a slowly-worsening problem. The car has something like 160K miles on it.

Sometimes when I'm at a stop and go to put it into 1st, it will go just fine.
Other times, it simply refuses to go into gear. I stop pushing the gearshift, let up on the clutch, push the clutch back in, and try to shift into first again. It then goes in, frequently with a crashing of gears.

I was guessing that some part that helps the gears mesh in the transmission (synchromesh rings? Sounds good :-) was wearing out, leaving the gears in a non-meshing position, and spinning part of the transmission (by letting the clutch out) gave me another shot at getting the gears to line up. But I spoke to a mechanic who come recommended to me, and he said that more likely it was leakage in either the clutch master or slave cylinders. This leakage would make it as if I had slowly let out the clutch, even though I had the pedal to the floor. Then, because the clutch wasn't fully disengaged, some part would be spinning, and it was this spinning that prevented me from shifting into 1st. I find this very unintuitive, but then I really don't know squat about transmissions.

It is also the case that the clutch is wearing out; I'm starting to detect slippage when I accelerate hard. This mechanic proposed to change out the clutch pressure plate, disk, slave cylinder, pilot bearing, and fluid for $880 parts & labor. We didn't really discuss how this would fix the shifting difficulty, but my thinking is that replacing the slave cylinder while he's in there working on the clutch would make sense (if indeed his analysis is correct); then if I still have the problem we could work on the master cylinder.

Can anyone tell me if this is even plausible?

Thanks

 

Yes almost all of the above "could" be an issue. I have to ask when was the last time you have the fluid in the trans drianed and filled? If it has not been changed in a while I'd start there as it will cost way less than a new clutch.
At 160K, on the original clutch, you are getting close to needing a replacement...

 

Interesting you should mention the fluid. I had the oil changed just the other day, and the guy who does it for me (since Honda in their infinite wisdom put the filters on the I4 engines on the back surface where it's good an inaccessible) said "well by mileage you're due for a transmission fluid change, but the color looks fine. Let's keep an eye on it.".

So I'll take it in and get the fluid changed and we'll see what happens.
Could old fluid really cause the problems that I'm perceiving as the clutch slipping?

 

What happen if you shift into 2nd then 1st ? I had to do that with my 97 3kgt, if i go straight into 1st it will grind most of the time, but if i go 2nd then 1st it will be just fine, i drove it like that for a couple yrs before i sold it, never get worse.

 

Are you asking about downshifting while decelerating or do you mean when you're just sitting there at the red light? I can't say that I do much going from 2nd to 1st in either case; when decelerating I tend to go from 2nd to neutral and just coast down to a stop using the brakes. It's never occurred to me to try going into 2nd before 1st at a stoplight. When you do that, do you let the clutch out any while you're in 2nd? I'll give it a try.

 

I had to do that at a stop, from neutral, clutch in, shift to 2nd not all the way in 2nd but into the gate then go into 1st and clutch out and go. Kindda confusing eh ?

 

I'll try to remember to give it a try. I'll have to un-train myself from my current habit.