FJ40 4 Speed Manual Oil Change (1 Viewer)

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Mount Pleasant SC
Hey ya'all. I have a new to me 1972 FJ40 w/ 4 speed manual transmission/transfer case. Could you please provide sage guidance or point me to a thread on how to change the transmission oil? I can locate the drain plug, but cannot figure out the fill plug. Thanks in advance! Tom
 
A picture or two of which transmission is installed, since a '72 never had a 4 spd from the factory, would really help. Right and left side showing the bottom would be useful.
 
OK. Here's some pics. It is far from stock. Chevy V8, original transfer case (as far as I can tell) and I assume a later year 4 speed trans. I hope these picss are not too vague. If more would help then please let me know. Any input is appreciated!

Tom

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Drains circled in red. Fills circled in blue. Good idea to check both fills first before draining. Reason is: if the internal seal has failed, fluid will move from one to the other. Removing fill plug first allows you to see if one is overfilled from this migration.

5763B600-3FC8-406E-930E-9867FE36C47B.jpeg
 
Brian and Skreddy. Just the info I needed!

I think I see what you mean by the PTO panel.... are there usually bolts there? Strange that one was left. Do I need to worry?

I'll definitely check the fills first. Is the hose add-on connecting transfer to transmission to help with the leak worthwhile?

Again, thanks for the info. I'm planning to replace all fluids and this is exactly what I needed.

Tom
 
that one bolt on the transmission Pto blank is for a clip that in my case holds the handbrake cable up out of the way.
 
The hose lets the migrating fluid level out between the two so its a non issue other than you have a failed seal in there but the fluid gets leveled via the hose connection, when moving it "pumps" fluid past bad seal overfiling one and hose lets it level. There has to be full fluid in both , if it leaks to a low level the hose becomes mute as it fills one while drying out the other so starting fluid level in each is a crucial discovery to start with. IMO your leak is clean fluid thats good . could be splines inside e-brake drum, could be seal of drum ( most likely ) , could be rear cone cover as people plug weep hole with silicone ( common ) , could be the idler shaft where it pokes thru rear of case ? For the hose if you need that use something bigger than 3/8th as IMO if its moving fluid and your running at speed it needs to keep up so one unit doesnt get over full while driving.
 
The hose lets the migrating fluid level out between the two so its a non issue other than you have a failed seal in there but the fluid gets leveled via the hose connection, when moving it "pumps" fluid past bad seal overfiling one and hose lets it level. There has to be full fluid in both , if it leaks to a low level the hose becomes mute as it fills one while drying out the other so starting fluid level in each is a crucial discovery to start with. IMO your leak is clean fluid thats good . could be splines inside e-brake drum, could be seal of drum ( most likely ) , could be rear cone cover as people plug weep hole with silicone ( common ) , could be the idler shaft where it pokes thru rear of case ? For the hose if you need that use something bigger than 3/8th as IMO if its moving fluid and your running at speed it needs to keep up so one unit doesnt get over full while driving.
Thanks all for the latest info. I replaced the fluids in trans and transfer. I'll go back and pop the fill plugs to see how much migration there was. Appreciate ya'all. Tom.
 

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