Gearbox whine but trouble finding the issue.

Well, so I played with mock up spacers for the diff. Sliding the diff laterally side to side made no difference in mesh of the gears. The play seams to be that the bevel gear needs to move downwards towards the mating gear so that there is no play between the gears. I, however, do not see how there could be any adjustment for this type of movement. The play really does not seam excessive between bevel and mating gear other than there is a very small nick on the outside edge of the face of each tooth on the bevel gear (only on one side of each tooth so this is directional contact at work). However, after really cleaning the mating gear I see very slight wear on the face of each tooth corresponding to the marks on the bevel gear but there are no marks on the mating gear other than that slight bit of wear.

Could a bearing really cause the bevel gear to "rise" upward away from the mating gear? I can only see how a worn bearing would do just as you previously said and affect laterally tolerance which doesn't seam to be the issue I currently have. I don't have a lot of experience with diffs so it's entirely possible the play is actually fine and some other issue is at work.

 

After an appointment in the morning, I'm going to get the gearbox back in the car. I'm not sure how, but after cleaning the CV flanges, pulling the bearing cups out, inspecting the tapered carrier bearings, cleaning everything and then reassembling the unit there is now zero play. Actually, it requires a little bit of force to rotate the bevel gears now but before it would rotate with very little force necessary.

I'm curious if it is normal for the bevel gear to require a bit of force to rotate it against the mating gear? Is it possible that there is now not enough tolerance between the two? Also, any ideas as to how a minor disassembly could make such a drastic difference? Perhaps one of the CV flange center bolts was loose?

 

Amen brother! I should have an update later tomorrow after going for a drive.

 

Quick question. I tightened the ringnut for the flywheel and installed the whole pumpkin assembly as one whole unit. Then, I tightened down the grub screw into the flywheel ringnut after install. Is this correct? I've read a few different threads and there are many opinions on the ringnut/grub screw procedure.

 

The clutch flex line stripped so I had to have Earls make a new one for me. I've got it all back together other than the shift cable junction just in front of the gearbox. It was installed incorrectly prior to me purchasing the car and now I've got to adjust the cable-to-clevis points and tighten those nuts up. Then should be all good to do for driving tomorrow and Saturday.

I've got the original cats that have been hollowed out that are free to whomever may want them.

 

Sounds good Ernie!

 

Went out for a drive today after Ernie assisted in getting the shift cables adjusted and looking over the car. When coming to a stop the car still makes a whining noise on deceleration although it sounds a little different. The noise goes away as soon as I press the clutch pedal in so I'm thinking the main issue now is the throw out bearing. The shifting is better than it has ever been after adjusting the cables and I'm not going to worry about the whining noise until after I do the engine out this winter and I will replace the TOB at that time.

 

Car is driving great but I'm going to park it for the season. After really giving it some thought, my issue can't be the throw out bearing. I'm leaning towards a bearing on the main shaft. I looked them over and all appear fine but I think I will go ahead and wait to pull the engine and go through the gearbox over the winter with a little bit more thoroughness. Time will be on my side!

 

Okay, fingers crossed but I'm going to give it one more go tomorrow. The gearbox oil level was just over the minimum mark at about 1/3 the way between min and max level. So I added about almost a quart of Red Line NS and will take her for a spin in the morning to see if perhaps the oil level in the gearbox might be a little low??? If not then I will take a stethoscope to the gearbox to see where the whine is originating to give me a direction during the winter on the engine out service. I also replaced the ignition coils with new Bosch units to verify compatibility. Will update tomorrow.

 

He heard it while driving behind me just not sure what it is exactly. I put the rear up on jack stands and had my brother go through gears at around 2k-2500 rpm and there was absolutely no noises coming from the gearbox using a mechanics stethoscope. It is RPM dependent and appears to need to be under load. I had thought about perhaps a pulley but that shouldn't require a load if that was the case. I'm completely stumped.

 

updating the thread. Here are a couple pictures of the ring and pinion gears. There is a lot of wear which is indicative of the noise I was hearing.

Can the ring and pinion gear surface be hard chromed and then machined back to spec? Any other fix rather than replacing the set? $$$$ Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login

 

Yup, anybody know of any ring and pinion sets for sale?

 

After looking at it and taking my own pictures I think this ring and pinion might be able to be REM polished, then installed and set up properly so it meshes correctly. Anybody disagree? Image Unavailable, Please Login
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