Posted by John W. S. son of John S. [162.158.78.187] on Friday, March 02, 2018 at 09:13:12 :
In Reply to: Noise? 52 power wagon transmission posted by George [172.69.22.179] on Thursday, March 01, 2018 at 21:40:45 :
George,
The later or second series non-syncro / crash box transmissions are inherently noisy in third gear. The reason is the lower cluster gear spins faster and faster first through third. The reduction of noise in fourth / direct because the cluster is now in an unloaded state. It is still spinning and throwing oil, but with no drive load it can find its happy place and not make as much noise.
Additionally, there is an idler on the PTO that also turns with the transmission input shaft.
Written descriptions of the various noises the gear cases on these trucks make sometimes leaves a little to be desired when it comes to how "bad" is bad enough to cause concern.
I have driven trucks that make a whining or clattering noises and others to the point where it sounds like the transmission is trying to come through the floor boards until shifted into direct. We pulled this one for repair and did not find anything really noticeably worn or loose internally. There was something not right for sure, but without it being obvious its difficult to troubleshoot.
As others have said, check your transfer case, differentials and drive line angles. You might find something that needs addressed, however it may not be related to the noise you are hearing.
A couple of other things to ponder like how well does your transmission shift? Did you see any odd / sharp wear patterns on the gears or shafts when you replaced the bearings? Did you check the PTO idler backlash when you had things apart? Is the shifter handle tight in the top? Does your truck have locking front hubs? The shifter and locking hubs should not make noise, but could give some indication how much other component wear might be present.
If you decide to make a boat anchor out of your existing transmission and find another for the truck, I would consider and early / fist series crash box or a snycro-mesh 420 from an M-37. The information on what plays well together and what does not, if you are not familiar, is in the archives or you can ask.
Good luck,
John S.
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