Borg warner oil?

[MysteryTheatre]

The manual calls for ATF dex lll , which seems a bit weak, since many chains break, , i have read recommendations for an MT- 75 weight fully synthetic , has anyone used anything other than atf in theirs?
to tell you the truth i don't like having a chain driven transfer case, especially one lubed with such a thin oil. also wondering how often should i change the oil, is once a year enough?

[Elemental]

DO NOT USE A THICKER OIL! You will burn the thing up. The reason the BW uses a thin oil is because it has a pump to pump it to the top of the case. The LT cases use a thicker oil because it relies on 'Splash' to get the oil around.


The chain isnt as strong as the gear driven Lts, but I wouldnt loose any sleep over it. Its pretty stout.

[MysteryTheatre]

thanks elemental, you are exactly right , while i asked this question to the forum members here, i also asked the chief engineer at BW, whom , responded in less than 24 hours with identical input:"The design was intended to run with ATF. These units have the floating pin style pump. Heavier / thicker oils will not be pumped correctly by this pump especially at cold temps.Higher driveline torques as a result of larger tires and higher power engines will shorten the life of the chain. Remember, this is a 13-61 double offset unit. The chain handles all vehicle torque and should be changed out more frequently when used in modified application."

I will continue to service this unit with the highest quality dex lll i can find,
any suggestions?
is synthetic recommended?
is refilling the unit once a year enough ?

thanks again elemental, you're incredibly helpful

[Elemental]

You're welcome. And, you are makign me blush.

Heres my experiance with these boxes... They are pretty sturdy, and hold up pretty well changing the fluid every 30,000.

However. 2 quarts of fluid is cheap...And easy to spill and fill. A guy coudl change it every oil change and not do any harm to anything more then his wallet. Smell it after it drain though. The Viscous Couplings in these sometimes leak the fluid and mix with the dex. ANd, it smells like crap! Its horrible. You will know it. IF it stinks, the VC is failed and you are not getting 4wd.

[MysteryTheatre]

thanks again elemental, YES fluids are cheap and repairs are expensive. a qt of dex lll is 2 bones so the whole job costs 4 bucks and a rag. i use the spout from a GL-5 bottle and screw it onto the atf container... the easiest way i have found.
if we go back to viscosity index' super 76 has a multi atf that has an incredible 208 viscosity index! the highest i have found, it blows royal purple(190) out of the water for less than half the price.