I actually looked it up.

People have run everything from Dexron ATF to 50w. No clutches.

So the syth motor oil will work just fine.. and since the rebuilder has a vested interest, I'd use what they suggest.

Maybe they use a cheaper chain and that's what the chain mfr calls for.

Well, I'm changing my mind on that. Found on Ford-trucks forum where everyone said Dexron.

I'd call the supplier and find out WHY they suggested the motor oil

 

I'm going to have to agree with you, ATF is made specifically for Tranny or T-cases.

 

I would not run any Xfer case married to an auto trans filled with anything other than ATF. Reason being if the input shaft seal goes out you get gear lube or oil in your trans. That usually = death for your auto trans. That is why the 208 and 241 were designed to use ATF for lube. You can use 5-30 in them without harm. But I advise against it if you have an auto trans.

 

I bought my remanned 208 from the guy who used to race the Kodiak monster truck, and now rebuilds t-cases and diffs for monster trucks and pullin' trucks, he says 5w30 full synthetic only.

 

thats new to me. ive never heard of anyone running oil in a 208. its kinda one of those things where i doubt it will hurt anything but just kinda strange