Re: 2003 overlander rear diff questions/help
5 table spoons a night means someone WAY overfilled it, or the seal is completely toast and he parks it face down on a 50 degree hill.
That is the pinion seal, alot of people do it differently and MANY do it wrong, really to do them your supposed to jack up the rear of the vehicle, remove the rear wheels, calipers and rotors... disconnect the driveshaft, then measure turning torque of the differential (a dial torque wrench on the pinion nut). from there you rip off the pinion nut use a puller on the companion flange and pull the seal, replace with new (I like to use anaerobic sealant on the outter sealing surface and lube up the inner seal surface with white lithium grease (if it didnt come prelubed). install new pinion nut and torque until it snugs up then a little more, measure turning torque and tighten pinion nut until it is back to what it was.
ALOT of people either mark the pinion nut to pinion gear orientation and just tighten the pinion nut until the marks line back up OR just rip it on by feel with an impact (yikes). the first WAY overtightens it, the later... yikes.
Its a decently large job BUT unfourtunatly its a job you dont know if its done properly unless you do it yourself.
btw there is no drain, you pull the entire cover, the cover and diff housing need to be cleaned, new rtv used and bolted back together after a good cleaning. On the overland you need some Mopar LSD additive or the clutchpacks will bind and chatter.