H22 trans randomly started grinding into 2nd...

[eazyduzit509]

Its been awhile since ive posted, but as it says... Ive had this M2A4 prelude transmission in my F22a accord for almost 2 years now. Ive had absolutely no problems with it, every gear shifts like butter at every RPM. Until today.

Came home last night and bumped up my mile long dirt/snow driveway as i have everyday, started my car up this morning and headed off to work, as i shifted to second it grinded... wtf? i get to a stop light and accelerate through my gears, again, grinds going into second... Whether it be 2000rpms or 6000. Eveytime... No idea why. Every gear is perfect except for 2nd.

Jacked it up tonight and checked my fluid level (Honda MTF as always) and it was ok. Topped it off with 1/4 of a quart and put it back together. Checked my shift linkage cables going into the transmission and they wern't obstructed by anything.

So my question is... WTF? Why would it just randomly start grinding, not even a build up to it, its always been fine. It disengases just fine, doesnt pop out of gear, ACT clutch has worked out well, everything... This is new to me and im pissed off, no idea why it would do this. I dont beat the car up, no highreving, gear banging madness... Ideas???

Thanks, Eazy

[CB7_JAY91]

Sounds like a syncro to me :'( I had this issue on my old F tranny, it'll get so bad that it'll wanna pop out and you'll have to a.) double clutch to use that gear, or b use that H22 torque and go 1 - 3

[TheProfessional]

Sounds like the synchro's on that gear are going or gone. Could be a starting trend, it'll definitely be the case if other gears are taking on the habit.

[Losiracer2]

your syncro is shot. Replace it. Things do wear out overtime you know.

[eazyduzit509]

Im aware things wear out. I know how a synchro works. The part that got me was the sudden full on grinding. Not a little hear and there over the months. From perfect to terrible overnight. Appreciate the replies, gonna try some synchromesh when I do my axles tomorrow and go from there.

[wed3k]

could also be a chipped tooth. ive seent it

[turbo90accord]

Synchromesh didnt help anything for me. I switched to redline MTL and shifts like butter.

Once a synchro goes though, no fluid is going to fix it.

Curious though, if your fluid level was fine, why did you add another quarter quart?

[eazyduzit509]

It was "ok". Hardly low. Not enough to make me worry. I JUST put in amsoil synchromesh, little smoother but still grinds... No metal chunks or synchro particles that I saw.

[h22sparkle]

Just becuase you dont see the shavings in the oil doesnt mean that the synchros dont go bad. If your car competant you can change out the synchros yourself or you can send it to gearspeed inc they specialize in rebuilds.

[Losiracer2]

Synchromesh didnt help anything for me. I switched to redline MTL and shifts like butter.

Once a synchro goes though, no fluid is going to fix it.

Curious though, if your fluid level was fine, why did you add another quarter quart?

Whatever you do DON'T use this stuff. the weight is 75w90....that'll royally screw up your bearings and you'll have whining gears in no time.that's what happened to my m2a4 after 3 months. there's a reason why Honda recommends 10w30

[turbo90accord]

Whatever you do DON'T use this stuff. the weight is 75w90....that'll royally screw up your bearings and you'll have whining gears in no time.that's what happened to my m2a4 after 3 months. there's a reason why Honda recommends 10w30

Everyone has different experiences, we use Redline MTL in 900hp hondas with stock gears with no problems. 10w30 degrades under extreme stress.

[eazyduzit509]

Little update. Have about 1000 miles on GM synchromesh, seems its helped. I'm still curious, in the morning when I drive the car and the tranny is still "cold", it shifts great for a good 10-15 minutes. I can drive to work without it grinding at all. As soon as everything has warmed up it starts grinding. Then just gets worse and worse until I let it sit awhile. One would think the viscosity of the MTF is thinning out with the warming, why else would it only grind when hot? I'm not denying the fact that I may need new synchros, but its got me thinking, maybe I can try the redline MTF or something thicker than the synchromesh (seems pretty thin, much like typical engine oil) it won't "break down" as much with the heat and help cushion a little better. You would think if a synchro is gone, its GONE. not only grinding when warmed up.

Maybe the synchromesh friction modifier?

Thanks, Eazy

[PR CB7]

Try adjusting you clutch pedal, almost 95% of honda owners fuck up their trannies by noy adjusting they pedal

A leaky cmc will cause your problem, since in a cold morning will hold pressure but a few pumps down the road, it wont be pushing the slave that far, most people wont realize a oem systems will work on heavy duty clutches, but dont excpect them to last 2+years

Losi is right, I swapped to redlne for about 2 months, thicker oils WILL cause bearing humm
When you have 900hp cars, a hum is the least of your worries, but it is for me, it can get annoying sometimes

My m2b4 started.grinding 2nd 6mo ago, but only on hard accel, keep using honda and concentrate on the rest of your drive train

[eazyduzit509]

Gotcha. I will check my hydraulic system. My slave and master are about 6 months old. In the beginning I was having issues with my clutch pedal adjusting itself. It was a mechanical issue, something under the dash in the mechanics of the clutch pedal actuation kept moving. I never did figure it out, but it has been ingaging about 1/2 up/down for a solid few months and has not moved.

What you're saying does make sense, but as for why it doesn't grind in every gear when that happens I don't know. During higher rpm shifts, my 3rd grinds sometimes. Never has before... also started a few weeks ago. I will look through the hydraulic, bleed, check for leaks and possibly adjust my clutch pedal (being that the pressure plate is pretty damn stiff, I can feel it farely well when I push the clutch in so I know its disengaging). Thanks for the input

[PR CB7]

the mechanical part of the clutch pedal doesnt get loose on its own
make sure you have the 3rd bolt on the pedal, to keep the pedal from deforming the wall when pushing, also make sure you remove all the free play of the pedal, some people think you can adjust the pedal but you cant, what you're adjusting is the rod of the master cylinder, in reality you are adjusting how far the piston move, the shorter the engagement the less the fork moves and the harder it is to throw the gears

it only does it on 2-3, because its the gears that get used the most, so without the fork engaging all the way, it will show what syncros have the most wear

6month on autozone equipment is really not that new

let me tell you how this happens

lack of fresh fluid
dirty moisture contaminated fluid, scores the walls of the pump, eventually starts leaking, making the pedal have a lot of free play/mushy feel, then since the fork is not engaging all the way it starts fucking up the trans, you can put goldshlager on it and it still wont help