Trans oil after 7 years (at least)

[giantsean 59]

Hey gang... been a while since I posted and nice to be back.  I've had the horses stabled for a while due to other projects... one of which I need my C-101 for now.  Last time she ran was about 2022 or so and that was a short haul.  Had to do some fixes to get her running (dirty points, bad fuel shutoff bunghole) - remedied and she fired right up.  I then remembered that if I ever changed the oil, it was back in 2019 when I picked her up.  Opened the drain and I'll be damned if the Stones themselves could paint that slop any more black.  Filled w/ 30W and refired.

 

I then thought ok as long as I'm on my knees for this woman, might as well take a peek between her legs.  Thinking she'd need a good enema, I had diesel and ATF at the ready.  Popped the dipstick and hot damn... pure honey!  I really can't remember changing the tranny oil so I will chalk it up to the PO changing it at some point.  It shifts fine and other than a few bubbles which I'm guessing were from it sloshing around, does not appear to have any water on the stick (she is stored in the shed).  I took some pics anyway... what say you guys?  Change it, or send it?

 

Thanks!

[oliver2-44 11,483]

Check that transmission oil after it has run in gear awhile. The crud very well could have settled out over several years.

[8ntruck 8,868]

I'm guilty of old oil in my transmission as well - it has been a good 6 or 7 years, maybe more.  Still clean.  A change is on my to do list sometime this summer.

 

But, I've run across a couple of articles about old oil.  Seems that the additive packages  (things to improve extreme pressure performance, viscosity additives, etc) in the oil have a shelf life.  After a period of time, the additives don't remain blended with the oil properly.

 

I'm going to say that a change of transmission oil every couple three years would be a good idea.

Edited 5 hours ago by 8ntruck

[giantsean 59]

Thanks.. I was kind of excited to give it a flush, thinking it was far worse.  But I'll drive it a bit and see how it looks as advised.

 

The other thing I can't wrap my head around... why does the drain plug angle UP?  Feels like there is a whole void in there that will never properly drain.

[cleat 8,980]

There is a drain plug on the bottom of the transmission to get all the oil out provided you lift the front of the tractor.

 

[giantsean 59]

Ahhh... got it.  They really needed more photos in the 10,000 different manuals they published

 

In that case, what in fact is this plug for?

 

[mrc 1,076]

giantsean,

 

tranny oil looks ok. 

but, when in doubt...change it out. 

2 quarts of gear oil is cheap insurance for your tranny. 

[kpinnc 18,252]

1 hour ago, giantsean said:

In that case, what in fact is this plug for?

 

In the early days of the Unidrive, there was no top oil fill. The side fill was all that was on many transmissions. 

 

The first 6 speeds in 1967 (and maybe others) added a short nipple to allow higher fill. Similar to the pic below. 

 

Eventually Wheel Horse added the top fill tube and dipstick.