NOISEY GEARS AND VIBRATION

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B'cuda

B'cuda

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69 barracuda 355 8.75 , green bearings, offset shackles. The gears make a high pitched hum when I'm on the gas but not when coasting but at 55 mph I get a harsh vibration that stops as soon as I let off the gas. Going faster somewhat smoother but not gone. Gears? Gears and driveshaft? Thanks for your opinions I don't have the funds to just replace it all.
 
sounds like its set up too tight or the pinion bearing is loose taking out the gear clearance causing them to lock up
 
teringer said:
sounds like its set up too tight or the pinion bearing is loose taking out the gear clearance causing them to lock up
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Thanks , the diff came from a junkyard years ago and well broken in, do you think the gears could still be set up ?
 
I borrowed a 323 diff from a 66 b body but couldn't get the drivers side Axle to seat. Stopped about 1/8 " short. Passenger side went right in and both axles work in the 355. Didn't see any obstruction or rust
 
I have read there is a center spacer in the diff for taper bearings that should???? Be removed for green bearings. Dont know if this is accurate but might acount for one axel not seating????
 
Check for a frozen U-joint or what I have seen done in years past is people forget to install the two C clips on the u-joint caps that fit into the rear end yoke. These center up the u-joint in the yoke. Without them you will get a vibration.
 
Dana67Dart said:
I have read there is a center spacer in the diff for taper bearings that should???? Be removed for green bearings. Dont know if this is accurate but might acount for one axel not seating????
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Can anyone one else verify this? I wondered the same
 
oldkimmer said:
Is it a 741 case with factory gears? If so they will always whine. Check ur u joints first for the vibe. Kim
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489 case from a 70 runner original gears, seems like a little end play on the pinion , no leaks
 
B'cuda said:
Can anyone one else verify this? I wondered the same
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That is a fact. The cone style SG used a one piece thrust button, the Dana Clutch style used a three piece thrust button. Both accomplished the same thing. The butt of the axles pushed on this button. Axle adjuster on the left axle adjusted the tapered bearing cones onto the tapered bearing. Green bearings do not need the thrust button and need to be removed as one axle will not go all the way in do to these buttons. Or you can short one or both axles.
 
I sure what I'm about to say is a BAD idea, but for a VERY temporary situation you might be able to shim both axles out enough to allow clearance, do a road test and see if your vibration and whine is still there.

AGAIN I am sure this a really bad idea.
 
SGBARRACUDA said:
That is a fact. The cone style SG used a one piece thrust button, the Dana Clutch style used a three piece thrust button. Both accomplished the same thing. The butt of the axles pushed on this button. Axle adjuster on the left axle adjusted the tapered bearing cones onto the tapered bearing. Green bearings do not need the thrust button and need to be removed as one axle will not go all the way in do to these buttons. Or you can short one or both axles.
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How much trouble to get the spacer out of the rear; involves a tear down?
Would it be easier to go back to timken bearings on the axels?
 
Yes u need to take the pin out then the spacer then re install the pin. U will have to remove the crown gear so that means removing the carrier assembly. If u go back to Timmons u will need the adjuster for the passenger axle. Kim
 
Dana67Dart said:
I sure what I'm about to say is a BAD idea, but for a VERY temporary situation you might be able to shim both axles out enough to allow clearance, do a road test and see if your vibration and whine is still there.

AGAIN I am sure this a really bad idea.
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I think I may have gotten off track; the gears in the car are 355s 489 case, whiney, noisey and have a vibration at 55 on the gas.
I have a back up gear set; 323s 489, that the drive side axels won't go all the way in. Sorry , probably should have made two posts in hindsight.
 
Do both have a suregrip? If so There is a spider gear and a cone on both sides that have splines and the have to be lined up for the axle to go in. Is the spacer in the 1st set of gears taken out. Is it in the second set of gears. If either set of gears are in the housing all u have to do is shine a light down the axle tube. Do u see a spacer or just a round pin? Put the other axle in first then see if it fits in lol the way. Yes or no. If so install other axle. Does it go in all the way? Kim
 
SGBARRACUDA said:
Check for a frozen U-joint or what I have seen done in years past is people forget to install the two C clips on the u-joint caps that fit into the rear end yoke. These center up the u-joint in the yoke. Without them you will get a vibration.
Click to expand...
Hey a victory! The u joint checks out okay but had small movement in one of the yoke saddles, no matter how tight ( 3/8s bolt, small joint) so I shimmed the strap .030 after squareing the ends up with a file and test drive.......no vibration, from the rear anyway, still have the gear whine to live with. I like the 355s but I live in the country where the first stop light is more than ten miles away and the 323s cold be built while I drive
 
oldkimmer said:
Do both have a suregrip? If so There is a spider gear and a cone on both sides that have splines and the have to be lined up for the axle to go in. Is the spacer in the 1st set of gears taken out. Is it in the second set of gears. If either set of gears are in the housing all u have to do is shine a light down the axle tube. Do u see a spacer or just a round pin? Put the other axle in first then see if it fits in lol the way. Yes or no. If so install other axle. Does it go in all the way? Kim
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The 323s are sure grip, and I believe are the cone type, I can check in a minute, I borrowed them, and don't know if any spacers were/ are installed, I'll see if I can tell, I don't have any loose axles at the moment
 
oldkimmer said:
Do both have a suregrip? If so There is a spider gear and a cone on both sides that have splines and the have to be lined up for the axle to go in. Is the spacer in the 1st set of gears taken out. Is it in the second set of gears. If either set of gears are in the housing all u have to do is shine a light down the axle tube. Do u see a spacer or just a round pin? Put the other axle in first then see if it fits in lol the way. Yes or no. If so install other axle. Does it go in all the way? Kim
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This is the 323s with the axels problem, both sides are 2 7/8" deep and have two rows of splines that are lined up and have a shiny disc at the bottom, pass. side looks to have a pin in the center
20180715_201112.jpg
20180715_200524.jpg
 
You have two options.
1) remove the third member and remove the thrust button
2) shorten one or both axles
But if you go with #2, you won't be able to go back to taper bearings
 
The early green bearings crimp style MP sold required button removal. The newer snap ring type do not.
 
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