Thread: Flappy whiring sound, maybe transfer box?

I have the transfer box out. Haven't taken it full apart, but everything looks OK. input gear was covered in oil and perfect condition as are the bearings and gears I can see so far.

I also have the gearbox out as I'm suspecting layshaft bearings. I removed the extension housing. My goodness that output shaft collar is tight! I was at max on a 10T hydraulic puller.

Removed the clutch also as I will replace this while it's out. Unknown history to me at 170,000kms.

Here is some pics and comments/questions.

Clutch. I have no idea if this looks OK?






Layshaft:





I spun the gears around but they all look good to me.

The bearing rollers are what I thought might look bad - but they look OK do you think?

Amateur question... the inner track has obviously stayed on the shaft and come out of the bearing. Is it suppose to do that? I take it that's not how it was fitted. Is it essentially a one time fit and now I have to replace it because it's been pulled apart? OR does that indicate slack in the bearing and maybe an issue? (then subsequently pulled apart easily)

Possibly the biggest point last - the layshaft nut is loose. I can spin it 2-3mm left to right. It is only restricted to 2-3mm because it's staked. Could this be the cause of my noise? The workshop manual says it should be 220Nm! So clearly I'm replacing some parts there, but it would be good to know if I've actually found my issue as I continue disassembling, etc.

Cheers.

Ok, never mind the bearing track question. It's suppose to be on the shaft. I read the manual.

Justin

Did you figure this problem out. I have a flapping noise under deceleration that sounds similar to yours. Just in proces of pulling the tranny but I am not sure what to look for

Cheers

Tim

Firstly, you should make sure prop shaft nuts and handbrake are all in good condition and torqued up correctly. They are prime candidates for a flapping noise. If you're still sure it's gearbox related, this is what I found:

In 1 go, I rebuilt the gearbox, transfer box and installed a new clutch. The noise is gone now and been fine for a few thousand kms now. So difficult to say what it was for sure, however the gearbox input bearing was pretty bad. When I pulled the rollers off, it looked like this:



A few of the other gearbox bearings were discoloured. I also found the 5th gear on the layshaft had a very small amount of float due to the layshaft nut being loose. It was only held in place by the stake, but still able to rotate a few mm's.

The transfer box was generally in perfect condition. If I had of known, I would have left it. Not a mark on any bearing or gear. In retrospect it was a waste of new bearings, but I didn't know that then. I did however replace the centre diff thrust washers which were worn down.

Clutch was probably original and looked pretty worn and changed for new while it was all out.

Good luck!

Thanks for the info. I have driven it with the front prop off and then the rear off with the front installed and it didnt go away. My noise is like flapping when I get off the gas

[ame="http://youtu.be/5tz_XA67Ghw"]http://youtu.be/5tz_XA67Ghw[/ame]

I am pulling the gear box but am only looking for the obvious as I have never had one appart before

Did yours sound the same as this? If so. With what you did, what would you check first

Cheers

Tim

Yep that sounds very very similar to mine!

I had never seen inside one either. One thing I learnt was there is little point in going half way if the box has many kms on it. To even inspect the gears and bearings, you're half way to a rebuild. To change bearings, you're 3/4 the way to a full rebuild, so might as well do the lot. Up to you of course.

To visually inspect all bearings you need to pull both main and extension housings apart to check all the bearings. That will leave you with 3 shafts full of gears and bearings on the bench. Inspect them. A badly damaged bearing making that noise should be obvious. Something like this:



Essentially if a bearing doesn't look new - it's damaged. There really isn't much in between.

Do you have a decent puller and press? You will need a big puller at exactly step 1 of taking the gearbox apart - the mainshaft collar. It is VERY tight.

Justin

Thanks. You are the only one who has heard that noise!!!!

I have no puller or press. I may bring it in to a local british car rebuilder who can work on this. I am considering ashcrofts or a used box but dont have the $2k to spend on this right now. Was hoping to fix it myself

Thanks for the help

Tim

Justin

Did you use the LR tool or just a regular puller. I do have access to one and have also found a used box for $300. I am going to get the used box then strip down my old tranny. I will ley you know if i find the same thing

If you have any photos of your tear down it would be great

Cheers

Tim