This past weekend I wanted to engage the 4wd in my 2000 Expedition (A4WD, 5.4L w/ 4r100) and there were strange noises coming from down below. Upon investigation, I found that my transfer case only had around 4 oz. instead of the 2 quarts inside. As I've always maintained my truck very well (i.e. changed fluids regularly), I presume the transmission shop that rebuilt my tranny several months ago didn't refill the transfer case.

Anyway, what kind of damage could be caused by running a practically dry t-case for an extended period? Could the seal between the tranny and t-case be the culprit and all the t-case fluid wind up in the tranny?

Thanks.

 

It's more common for fluid to transfer OUT of the trans into the t-case; Ford even published a TSB about that. It sounds like the trans shop screwed you.

I'd make them install a new (or at least reman) t-case since almost everything inside is probably damaged.

 

So are gears constantly turning inside the t-case even when not in 4wd?

 

Yes. Not ALL the gears, but some are. And most of the bearings are. Yours is a little different from this, but it's close:

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