2nd Gen Non-Engine/Transmission transfer case fluid

[dieselsam59]

i just changed my transfer case fluid. i replaced it with valvoline atf+3 . is this ok? the book calls for atf+4. I figured it would not matter because it is just a chaincase, but then when i drained the oil I saw what looked like a suction pickup for an oil pump inside. does it have a oil pump? should i replace the atf+3?

 

[y-knot]

If I was worried enough about the transfer case oil, that I changed it. I would put back in the same type fluid the owners manual recommended. I would think that if AFT3 was OK, then they would not have spec the 4. There is much more to the fluid then just something to lub a chain. Very often there are seal and other rubber like material to consider. These materials all react differently to different fluid types. Some seals "Swell" when exposed to certain agents and others shrink, some even dissolve. If it was just a "chain in oil" then there would be no need for a specific fluid type, you could run gear oil and it would survive. More and more manufacturers are using composite materials, these are wonderfully new materials that exhibit great qualities. But many also require special lubricants and or fluids that otherwise would not be needed. These material are found mainly in transmissions, they are used in clutch friction material, band friction material, torque converters, and on Meany other components such as seals and linings. These is one reason they specify certain fluids, to accommodate the newest technology.

 

[Joseph Donnelly]

Gen 2's use ATF +3 or Dexron 3. Gen 3s use +4.