Transmission noise

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RBW
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Transmission noise

Post by RBW » Mon Dec 13, 2021 4:25 pm

Ok - now that the Mule is driving, more problems reveal themselves. Transmission operates fine, shifts pretty well, vehicle has plenty of power and drives well. Has a fair amount of clattering in reverse, first, and second gear. Surprisingly smooth in third gear. Reverse and second are noisiest, both in low and high range. Almost reminds me of the clacking made by tank tracks. It's not excessive, but it is noticeable. I'm going to have to get into the bellhousing before too long. Based on some other water and long term storage damage I have observed, I'm guessing some of the upper ball bearings in the transmission that were not coated in gear oil for many years are trashed and will need to be replaced. Any thoughts based on these observations as to which bearings to check and how to gain access to them? Depot maintenance manual of course generally takes the approach that you are going to take the transaxle completely apart. It looks like much of this could be inspected/replaced by removing the front transmission cover, but I know these projects can sometimes be a can of worms. Probably will just keep it full of gear lube, drive, and observe for now.

Curtis


RBW
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Re: Transmission noise

Post by RBW » Sun Dec 19, 2021 5:28 am

OK - found the write up from some years ago about pulling the front cover. I'll probably just drive it a bit, check the drain plug periodically for residue, maybe put in a magnetic drain plug, do the shift shaft seals to keep the oil in (my main point of leakage right now), and plan another big downtime to pull the engine and front cover and see what's going on in there if the slow gear oil leak into the bellhousing doesn't get me first. Have do do the clutch cable as well when that time comes around.

Chuck W.
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Re: Transmission noise

Post by Chuck W. » Sun Dec 19, 2021 8:35 am

One thought that comes to mind, when you are in 3rd gear, the Main shaft and spur shaft are coupled together and turn as a unit, in all other gears, the two shafts rotate inside each other on the 3110-156-7721 roller bearing, (item 3 below). If it is bad, it might be the source of the noise, or it could be something in the sychro hub and rings.
Image

Be careful when putting your transmission back together, it it important to check the clearances between the synchro hub and the shaft.
viewtopic.php?f=148&t=318946&p=1857448& ... n#p1857448

RBW
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Re: Transmission noise

Post by RBW » Tue Dec 28, 2021 6:38 am

Chuck,

Good thought about the needle bearing. I am going to continue monitoring it and may try to poke around through the fill plug to see how much movement is in there.

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RBW
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Re: Transmission noise

Post by RBW » Sat Jan 22, 2022 8:41 pm

Chuck,

Your idea about the mainshaft was mostly correct, except I think the main problem is a very badly chewed up input gear on the countershaft cluster gear. Input shaft spur gear is in decent shape from what I can see, and all the other gears on the countershaft look good, but the one farthest aft has badly deformed teeth and lots of corrosion. Looking for a new countershaft cluster gear now.


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bms07
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Re: Transmission noise

Post by bms07 » Sun Jan 23, 2022 6:38 pm

Check with John Emery. He should have it.
Looking for halftrack to restore
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