C-120 8spd rear end fluiid

[truckin88 104]

Want to change the fluid on my C-120 8spd. How much fluid, I read varying numbers, the most consistant looks to be 2qts, and what type 75-90 or 85-140??

Do I just drain at the allen plug?

Thanks and tips are useful!

[dodge78 90]

I just did mine saturday. It took 2 quarts and I used 85-140 TYPE 5. Remove the plug on the bottom with an allen wrench. I used a 1/2" copper pipe in the dipstick hole with a large funnel wedged in to it and taped it so it would not fall off. Funnel to pipe that is.

Here is a picture of my old fluid but it sat outside for a year or two with practically no shift boot on it.

[Stigian 1,234]

Yuk, that oil does look slightly past it's best

Quite a nice pattern it has made in the bucket though...

Yes I know... Im a bit strange :omg:

[lotus1967 0]

Would this be the same rear end one would find on a 418? I.ve always used 90 wt.

[gwgdog66 23]

Would this be the same rear end one would find on a 418? I.ve always used 90 wt.

Yes, I downloaded a lube chart from one of the sites in the links section, and the 418-8 shows this:

T-3..SAE 90-140 A.P.I. Service GL-5 Gear Lubricant (No Service Interval)

I changed mine (C-160 8) weekend before last and it came out much like in the picture shown above. I went with royal purple 90-140 GL5.

[Astrolite 1]

Ok, back to the question on how much oil. I just changed the oil in my "75" C-100 and the dipstick shows it slightly over full at 1 1/2 qts. The service manual says 2 qts. Which is right? Has anyone else noticed this? My trans model is 5091.

[gwgdog66 23]

Mine did too. The first quart I filled from the fill hole right behind the brake band. It wouldn't take anymore there. I checked it, and it was barely on the stick. The second 1/2 quart I had to fill through the dipstick tube. It checked slightly over filled.

I ran it for a good two hours afterwards, and checked it the next day and it read low, so the unused 1/2 qt went in. No leaks anywhere, the top bottom and sides of the case were dry, no leaks on the garage floor.

Now it reads full every time I check it. Maybe I created some kind of air pocket by using the dip stick tube to fill it up.

[Astrolite 1]

Maybe that's it. I added the oil through the dipstick hole too and really haven't used the tractor since. I'll cut the grass as soon as it stops raining and check it again. Thanks!