203 transfer case questions

[NeslundB]

Hey guys. I'm swapping transfer cases out of my M880 with another 203, and I was wondering what fluid I'm supposed to run through it, and how much of it I use. I've found that you're not supposed to run gear lube through them (which I have been....oops. Probably why my case got blown.) Thanks

 

[11Echo]

Hey guys. I'm swapping transfer cases out of my M880 with another 203, and I was wondering what fluid I'm supposed to run through it, and how much of it I use. I've found that you're not supposed to run gear lube through them (which I have been....oops. Probably why my case got blown.) Thanks

Straight 30wt motor oil per owners manuals for 203 cases.

 

[NeslundB]

Straight 30wt motor oil per owners manuals for 203 cases.

Thank you. How much does it take?

 

[11Echo]

Thank you. How much does it take?

Been a while since I filled one.
In my GM vehicles with a NP203 transfer case you would fill them up to within 1/2" of the fill plug hole. Seems like like that was around 7 pints. Also, in areas of colder climate it was ok to run 10/30 instead of the straight 30wt.

In my "part timed" 203 cases I added a pipe nipple and elbow and filled them to the top for splash lubrication.

 

[Bob H]

Swapping out 203's! Those cases are HEAVY!
The capacity is listed in the TM's (which can be downloaded from this site. 2 or 3 quarts should get you there.

In 78 Dodge started specifiing 10w30w for the 203's. IIRC, I have read that 10w30 was a better choice, performance wise. I have only used straight 30w in mine so far.
Isn't straight weight oil "Non Detergent"? and multi vis oils "detergent"?
If that is correct then I would think the straight 30w would be better for the long term, since there is no filter to catch the particles that would get encapsulated in the multi vis oils.