COTTA TRANSFER CASE IN 1978 GARRETT SKIDDER

[BackYardLogger]

 Need maintenance help. Cotta transfer case in 1978 Garrett skidder. Does anyone know the proper lubricant to use in this transfer case?
This is a fairly new skidder to me, and would like to drain and replace the fluid, but not sure what fluid to use. Garrett 21A, 353 Detroit engine
with Allison 4 speed transmission. model # TR 1610-8 transfer case . Any help will be appreciated.

[mike_belben]

an all gear-driven, straight toothed, manually selected Tcase?


If so they can run about anything.  Considering that every automotive manufacturer has made them and spec'd every possible lubricant, generally speaking. Gear oils, motor oils, mineral oils and ATF off the top of my head.

A skidder has some high torque and abusive loads so id personally want a thick oil with a lot of wedge pressure to keep oil between the tooth.  Anything that goes in a roadranger will be well suited to that box, if its what im picturing.

[Satamax]

Could this help? 

Cotta Transfer Case Lube Plan | Lubricant | Motor Oil

http://www.gapvax.com/assets/pdfs/cotta.pdf

[Ed_K]

 I'm not sure what I'm reading in the T M it looks like it calls for a hydraulic type of oil? I've been running 80-90 wt oil in mine for 15 yrs and haven't had any problems. It had 80-90 when I bought it and when we went thru it 3yrs ago all that was done was speedy sleeves on the two bottom output shafts and the pto shaft. The bearings were still within tolerance.

[logman81]

80-90w will be just fine thats whats in my c4b.

[BackYardLogger]

Thanks all for your input to this post. It sounds like I have a lot of choices, 80-90, straight 90wt., 140wt. mineral oil, 220wt. synthetic. The synthetic was recommended by a local petroleum co. The Forestry Forum is a great resource, so much experience and so many different ideas. Nice people, too.   
 Thanks again, cheers .    8)

[Satamax]

Backyardloger. 

I think, as long as you have an oil, viscous enough in there, you shouldn't have trouble.

H46, or 30, something oil in tractors is sufficient for some tractor gearbox applications;  So 80w90 should plenty good i would think.