Don't know about a 'h/o'(high output) 4.0..

Never heard of rotors or calipers just falling apart..

Top the fluid off and see if the problem persists. The Tcase and trans take ATF(automatic trans fluid). The drain is just like a axle fill plug or any other type of fill plug....3/8" ratchet sticks in there and it's lefty loosey. To get to the tcase drain, you've gotta remove the 4 13mm head bolts that hold on the 'dynamic balancer' thingy on the back driverside of the tcase.

BUT...that's if youre asking about the transfer case. If it's the front axle, there is no drain. The proper way to drain it is dropping the axle out of the truck and popping off the differential cover.




Is it a constant grinding?? Meaning in 2wd or 4wd or anything? I'd suspect wheel bearings before I start thinking front axle or tcase. But again...top of the fluids and see if the problem persists then go from there.

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'01 XLT disguised as a '03 Fx4 Level II.