From the Eaton mechanical locker .pdf;
'Maintenance free, requires no lube additives'.
That's not clear enough, surely, given that 'lube additives' are in every lube of every kind beyond animal fat in a wooden axle. But the intent here is certain if not clear; the mechanical locker does not have the static load that a spring loaded limited slip does when it's not engaged, so doesn't need that lube slip added. Also this illuminates why they say it may delay engagement, because the friction of the discs is what forces the ramping and clamping of the disc pack.
The Eaton .pdf I found is all the way back to 2009, and makes no reference to lube recommendation beyond the above. Given the state of affairs with lubes in general, and changing sources/alliances/marketing/part numbers, I don't see any real way to be certain you have the 'best overall' or even 'OEM equivalent' lube, and given the different requirements of 4-wheeling a jeep trail with an empty 1500 or pulling a 10,000lb horse trailer behind the barn with your diesel dually, there may be no 'perfect' lube. Additionally, it's pointed out that pre-'98 vehicles have seals that like mineral oils, and synthetics may lead to leaks. I use Chevron Delo ESI in all my gearboxes; it's GL5 and has Mack and Meritor approvals, and has no indication that it accommodates limited slip differentials (which are never in heavy-duty axles, either). It reduced the bevel drive temperature on my Moto Guzzi 1100 by about 15*F.
FWIW.
'Maintenance free, requires no lube additives'.
That's not clear enough, surely, given that 'lube additives' are in every lube of every kind beyond animal fat in a wooden axle. But the intent here is certain if not clear; the mechanical locker does not have the static load that a spring loaded limited slip does when it's not engaged, so doesn't need that lube slip added. Also this illuminates why they say it may delay engagement, because the friction of the discs is what forces the ramping and clamping of the disc pack.
The Eaton .pdf I found is all the way back to 2009, and makes no reference to lube recommendation beyond the above. Given the state of affairs with lubes in general, and changing sources/alliances/marketing/part numbers, I don't see any real way to be certain you have the 'best overall' or even 'OEM equivalent' lube, and given the different requirements of 4-wheeling a jeep trail with an empty 1500 or pulling a 10,000lb horse trailer behind the barn with your diesel dually, there may be no 'perfect' lube. Additionally, it's pointed out that pre-'98 vehicles have seals that like mineral oils, and synthetics may lead to leaks. I use Chevron Delo ESI in all my gearboxes; it's GL5 and has Mack and Meritor approvals, and has no indication that it accommodates limited slip differentials (which are never in heavy-duty axles, either). It reduced the bevel drive temperature on my Moto Guzzi 1100 by about 15*F.
FWIW.
