'08 Transfer Case Fluid - Syn or Not?

[EddieC]

Owners manual note Dextron VI for our transfer case not mentioning synthetic or not..
In looking for the fluid I see semi-synthetic and full synthetic but not conventional based oils.

Being that the manual doesn't say what is acceptable and the GM product doesn't mention synthetic in its description, what is appropriate?

I hate using synthetics where they weren't intended because that often results in leaks in my experience.

 

[Yngbld32]

I use GM transfer case fluid only. Others might be different.

 

[TraumaTruck1]

I believe that all Dextron VI is synthetic. I believe that is what makes it the VI. That's why they allow you to substitute VI in the older cars, but not the other way around.

 

[ccapehartusarmyINF.(ret)]

synthetic motor oil gear oil is actually intended its engineered for the purpose the reason why you tend to get leaks with synthetic is synthetic oils molecules are smaller then regular oil so it will expose leaks in older vehicles that you would not normally see with conventional oil
Just use what it says in the manual u can never go wrong by using what it says in the owners manual
the tahoe xfer case with i beleive is a new process and uses Dexron III or (cherry juice) as we called it in the army

 

[EddieC]

synthetic motor oil gear oil is actually intended its engineered for the purpose the reason why you tend to get leaks with synthetic is synthetic oils molecules are smaller then regular oil so it will expose leaks in older vehicles that you would not normally see with conventional oil
Just use what it says in the manual u can never go wrong by using what it says in the owners manual
the tahoe xfer case with i beleive is a new process and uses Dexron III or (cherry juice) as we called it in the army

Maybe they changed the spec. My 2008 manual requires Dextron VIl.

The confusion lies in the fact that the GM (ACDelco) writeup for that lubricant doesn't seem to mention that it's synthetic but many of the other brand name replacements noted as Dextron VI in the parts store are either part or fully synthetic.