Whining Transmission: Help Please

[Marshall]

My transmission is starting to whine a bit when releasing the clutch, at the point of engagement. It only happened once, a week ago shifting from 1st to 2nd - but when I took 'er out today it seemed to happen in all gears, and even slightly when pressing clutch in, at same engagement point. The whine is short sometimes, and long other times, and if I really shift slowly, and release the clutch very slowly, then there's no whine. The most common answer I found online was to change the trans fluid. Is this the best place to start? If so, what's the recommended fluid for my '67, P Motor. Thanks!!

[RiverPatrol]

Sounds like it might be bearing in the trans. You can try changing the oil; use gear oil, 90wt or 80/90wt.

Does it make any difference if you shift into 4wd, lo or hi?

[jwgreen]

Could also be the clutch throw out bearing seeing as how it changes with clutch application. Either way you will have to pull the trans to fix it.

[Marshall]

Thank you, thank you.

It does happen in LOW, but only very slightly and only going into first gear. 4WD is the same, only slightly, and not very often. The majority of the whine happens in HIGH, going into 1st and from 1st to 2nd. But it's very sporadic, not every stop, not every gear change. Lengths of noise also changes from short to long.

[RiverPatrol]

Are you positive the noise is coming from the trans? When the rear axle bearings are going out the noise is very hard to isolate, and sometimes not even a whine but almost a chatter. I had someone describe it as "angry mice" once. The noise can be very inconsistent. When you hear the noise for a while, check the center of the rear wheels to see if either side is unusually warm.

[Marshall]

I am definitely not positive it's the trans. Being so green to vehicle maintenance, that was my first guess, and from what I read online. BUT, it sounds like your second guess could also be the issue. I'll check the rear wheel heat.

I'll also try catch it in the act on video and post it up. Thx

[Esteban]

Could also be the clutch throw out bearing seeing as how it changes with clutch application. Either way you will have to pull the trans to fix it.

Marshall, by what you describe, I think Justin is pointing in the right direction, with the culprit probably being the throw out bearing. The fact that the noise appears at the point of engagement of the clutch is a key fact.

Try first to take the carpet over the transmission hump. The noise will magnify a bit if it's coming from that area. And also, you can take the upper part of the body cover over the transmission and get an even better feeling of the noise. If the cover is out, work the clutch and you'll probably hear it every time.

The Parts Manual call this cover the "mission cover". In the following link it will be #1 and #2. Take #2 cover only.

http://www.carpartsmanual.com/nissan/pa ... sion-cover

[RMP&O]

Yup throw out bearing. Not that uncommon in any manual trans vehicle. Even play in mud/water can make them whine.

Cheers

[Marshall]

Thanks all for the advise. I haven't had the time yet to do the diagnostic tests recommended, but will post up results when I do. Thanks!

[moore_rb]

Marshal- one thing to keep in mind if it does happen to be the throwout bearing (which, I agree with the others here, is the most likely culprit) is that noisy throwout bearings can still last many many thousands of miles; and it may not be worth dropping the transmission, just to replace a $50 bearing... The throwout bearing can fail without taking out anything else around it, so drive it till it breaks (IMHO), or until the rest of the clutch needs to be serviced/replaced as well.