Without the actual service technical documents or a prescribed procedure I’d hold off on a transfer case oil change (or at least have the dealer do it). Judging by the different quantities of oil being drained out by various folks it suggests the oil cooler is playing a factor and there is probably a very specific procedure to make sure the cooler is drained and the exact right amount is put back in the entire system.
If for example, you catch the thermostat open and the entire system drains out but you can only get sufficient back in to fill the transfer case you’d be short the amount of oil that is supposed to be held in the cooling circuit. With no way to get the remaining amount in the fill port without it overflowing back out you’d be running the entire system low of oil. I don’t think you can rely on the fill port as a confirmation the level is correct like you can on most differentials.
I bet my left lug nut there is a fill procedure which requires certain temperature parameters be met and/or some kind of recirculating pump needs to be triggered electronically, or the transfer case needs to be ran with the vehicle on a lift stationary to circulate the oil in the cooler circuit before a final top up.
I’d would also like to be able to do the transfer case maintenance myself but would want to see actual service procedures beforehand. It would be an expensive mistake to make running the transfer case low even though you had serviced it with the best of intentions.
If for example, you catch the thermostat open and the entire system drains out but you can only get sufficient back in to fill the transfer case you’d be short the amount of oil that is supposed to be held in the cooling circuit. With no way to get the remaining amount in the fill port without it overflowing back out you’d be running the entire system low of oil. I don’t think you can rely on the fill port as a confirmation the level is correct like you can on most differentials.
I bet my left lug nut there is a fill procedure which requires certain temperature parameters be met and/or some kind of recirculating pump needs to be triggered electronically, or the transfer case needs to be ran with the vehicle on a lift stationary to circulate the oil in the cooler circuit before a final top up.
I’d would also like to be able to do the transfer case maintenance myself but would want to see actual service procedures beforehand. It would be an expensive mistake to make running the transfer case low even though you had serviced it with the best of intentions.
