Gear whine

Gasoline FumesGasoline Fumes New Wagonist
in Engine & Drivetrain
On a recent roadtrip, the '91 Wagon started making a pretty noticeable gear whine up a hill. It continued on and off for a few miles and then faded away. No problems at 70-80 MPH on the highway or in Times Square traffic. The sound didn't come back until a few hundred miles later at the end of the return trip. It made the sound while accelerating and deaccelerating in gear. I tried to get the fill plug out at a gas station, but I couldn't get enough torque on it from above. But it's never leaked and looked dry underneath anyway, so I'm sure it has fluid in it. Any ideas what it could be or why it would come and go? It's a 2WD wagon, manual transmission and 165k miles.

Thanks. :cool:

Comments

  • rallyrat427rallyrat427 Wagonist
    get that plug off ... sh*t burns off over time .. you should be changing it every so often anywas ... also, get some honda MTF .. outperforms anything else on the market and is fairly cheap
  • Gasoline FumesGasoline Fumes New Wagonist
    I put new Honda MTF in it a few years ago and I topped it off earlier this year when I replaced an axle. Whenever the clutch wears out, I'll either change the fluid again, or swap in my spare (better shifting) tranny. I will check the fluid, but I've never seen any "burn off" in a manual tranny.
  • JakerJaker familEE
    Do a search for ISB and let s know if that matches the symptoms you're experiencing.
  • bam-bambam-bam Council Member
    Also check wheel bearings :idea:
  • Gasoline FumesGasoline Fumes New Wagonist
    Jaker wrote:
    Do a search for ISB and let s know if that matches the symptoms you're experiencing.
    Based on what I just read, it doesn't seem like it's the ISB. The noise is only there with the car moving and either an accel or decel load on the gears. If you get the throttle just right, the noise goes away. Floor it or lift off the throttle and the sound comes back. I'm about to use the car again, I'll try to see exactly when it does it.
  • JakerJaker familEE
    If your ISB is sufficiently pooched, what you could be hearing is the gears meshing poorly because of the extra clearance between them from the inability of the input shaft to stay put. When that bearing fails in a big way, you end up with a lot of movement of the input shaft which carries all your gears. If the input shaft moves far enough away from the mainshaft, you could end up with enough gear lash to make some pretty substantial noise. Also, under just the right load conditions, the noise could go away. Closed throttle (coasting) leads to engine braking which will load the gears. Moderate to full throttle obviously loads the gears. Very light throttle will load the gears in such a way that the noise could go away.

    Otherwise, all bets are off. You'll need to rip the tranny apart no matter what. The ISB is the last bearing before the clutch housing, and needs all the gears removed to access it. Make sure you change the input shaft seal while you have it apart.
  • Gasoline FumesGasoline Fumes New Wagonist
    I've never been really happy with this transmission, the synchros have been slow since we got the car with 75k miles on it. I just don't understand why the noise would suddenly pop up and then be gone again.
  • HaydzHaydz Moderator
    The ISB on my L0 (Honda City box) did exactly that - came and went for a while. Sometimes it would only do it in third and fourth gear. Then one morning it just did it whenever the clutch was disengaged.
  • Gasoline FumesGasoline Fumes New Wagonist
    I hope it lasts the winter. My first thought was a bearing when the noise started, but I kinda thought a bearing would gradually start to make noise. So I guess I wait to see if the noise gets worse? I'm so glad I have an identical parts car in the woods. :D
  • Gasoline FumesGasoline Fumes New Wagonist
    I'm pretty sure it's the tires. :oops:
    It only happens on really smooth or wet roads. Brand new 155/80 WS-50 Blizzaks. I don't remember hearing the sound with the 175/70 WS-50 Blizzaks. :?
Sign In or Register to comment.

© Vanilla Keystone Theme 2025