68 John Deere 4020 clunking issue

Hey guys new to forum

Got a 68 4020 diesel that for some time growing up has made a kind of clunk noise when changing direction from reverse or forward drive gears. Doesnt do it all the time seems to really do it when you let the clutch out fast Tractor had transmission redone about 4 years ago Have heard and seen other tractor make the same noise didnt know if some one could narrow down the troubleshooting


Thanks.
 
Cory, welcome to YT. You say the trans was ..redone 4 years ago.. but what about it was redone?
Everything in the world could have been put it in the trans new, but if they didn?t touch the
differential or final drives a lot of things could still be making the clunk. There is a planetary gear
final drive inside the large part of each axle housing where they bolt to the trans case. Plenty of
stuff to get loose in there. If the hydraulic filters don?t seem to be getting a lot of filings in them
there is probably not a huge problem just more of a annoyance. Not saying you may not take it out
in the field tomorrow and have it stop on you because something stripped out. Have you checked
the wheels where they bolt to the axles for being tight, like no rust showing between them?
 
Thanks for the info
Synchro was rebuilt top shaft
They apparently went through it when my dad sent it off . Tractor has had transmission filter changed twice and haven?t really seen large metal particles.
 
Have you checked & see if your rims & wheel weights are tight? I had a tractor with loose rims/ weights that were loose & it made a Clunking noise. Dave F.54
 
(quoted from post at 21:46:40 06/18/18) Have you checked & see if your rims & wheel weights are tight? I had a tractor with loose rims/ weights that were loose & it made a Clunking noise. Dave F.54
Yes I have checked wheel weights and wedges they appear to be tight.
 

Have heard of this noise being common on the 4010 and 4020 tractors. Which to me when I hear it makes me turn my head and say oh hell that aint good other than that tractor runs drives great.
 
Our old 43 with rops cab always had a clunk my 3020 started
clunking after I moved the wheels in put a 4 foot cheater on
my 3/4 drive John Deere breaker bar and solved that problem
 
"didnt know if some one could narrow down the troubleshooting"


MOST likely, this is a case of "if it ain't broke, don't fix it".


There's a LOT of "final reduction" after the transmission components you mention, and a "clunk" is gonna happen after all that.

Check to see if the wheel centers are tightly clamped to the axles and the rims are cinched TIGHT to the cast centers.

Having verified that. if worried, you can check the sump screen and the area below it for metal flakes, and if you don't find more than a few of 'em, your tractor is simply doing what 'ol 4020's do.
 
It is not uncommon to find a 10 or 20 series that does that. I have a 3020 that has more of a crack than clunk when changing direction. It has 10,000 hours and is a loader tractor. It is just wear in the differential. I agree with the others just use it. Tom
 
Ours had a bad wedge in the cast center to axle when it did that. Put a mark on the axle and center and also at the rim to cast center. Then go and make it make the noise 1 time then get off and check your marks.
 
(quoted from post at 07:06:24 06/19/18) Ours had a bad wedge in the cast center to axle when it did that. Put a mark on the axle and center and also at the rim to cast center. Then go and make it make the noise 1 time then get off and check your marks.

Appreciate all the info just wanted to see if other people had the same issue with their tractor.
 
I had a 4230C with 3 weights on each wheel when purchased....157# each?....in addition to the cast wheel and rear end weight. I was on the wheel-to-
rim nuts all the time trying to keep them tight. Obviously the wheel distorted as the tractor rolled.
 

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