Transfer Case OIl

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Sep 17, 2006 | 12:08 PM

chefddh

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Transfer Case OIl

I need to refil my dana 20 trans case and my rear differential how much fluid do I need and can I use 80/90 gear oil for both?

Sep 18, 2006 | 02:56 AM

fordtrucksforever

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Yes the 80/90 works for both. Depending if all fluid is completely drained. At about $8 a gallon, two should get everything with some to spare.

Sep 23, 2006 | 07:54 PM

Tim Young

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From: North Central Washington

Quote:

Originally Posted by fordtrucksforever

Yes the 80/90 works for both. Depending if all fluid is completely drained. At about $8 a gallon, two should get everything with some to spare.

On my glove box lid it says to use 50W in the transfer case (maybe easer to shift in the winter). I have not asked at the parts store but I guess it would be available. But as fordtrucksforever said I think you will be just fine with 80/90.

Tim in Chelan

Sep 24, 2006 | 07:42 PM

fishmanndotcom

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From: Senoia, GA

in gear driven cases (Dana 20, NP205, etc) heavy weight (80/90) is recommended to help coat the bearings and keep them coated. in real cold areas such as northern states that see negative temps a thinner weight is recommended so that as the temps get colder the oil can stil get in the bearings and keep them coated instead of the oil gettin all syrupy!

in chain driven cases (np208, np203, etc) tranny fluid is recommended b/c the chain is harder to get oil coated on the inside so they use a much thinner oil. otherwise the chain would burn up

-cutts-

Sep 25, 2006 | 02:05 AM

fordtrucksforever

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One real problem with using 50W oil. Its readily available. I use it in a high milage truck just to keep oil pressure out of the red. Good truck, but very loose inside. In the Dana 20 transfercase, it will leak all over the place. The bearing plates and shafts are not gasketed, glued, or oringed. With the milage on these, you have clearance. And then there is a big mess everytime you stop. Next time I go thru one, its getting grooves cut in the shafts for orings and figure a simple way to seal the shimmed bearing plates. I really hate to silicone all of these pieces.

Sep 25, 2006 | 11:23 AM

RCrawler

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From: Southern Oregon USA

If the surfaces are clean, silicone works great on the endplay adjustment shims and will last a long time.

50 Wt Transmission oil (not the same as engine oil) is the factory recommendation for transmissions and transfer cases. I've used both and the only time I may have noticed a difference is in extreme cold conditions -30 deg F.

Jason