I'm going to replace the oils in my transfer case and differentials and wondering if there's any real benefit to one brand over any other. The transfer case doesn't list a spec but is there such a thing as a "premium" gear oil when it's not exactly dealing with everything engine oils do?
Is there any real difference in diff/transfer case oil qualities?
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@SubieRubyRoo created this thread just for this purpose:
That said, I've run Amsoil gear oils for the last several years but forgot to place my order when I had time to service my F150. I just went ahead with Motorcraft & am not worried about it.
That said, I've run Amsoil gear oils for the last several years but forgot to place my order when I had time to service my F150. I just went ahead with Motorcraft & am not worried about it.
WOW! Thanks for that!@SubieRubyRoo created this thread just for this purpose:
That said, I've run Amsoil gear oils for the last several years but forgot to place my order when I had time to service my F150. I just went ahead with Motorcraft & am not worried about it.
For instance, some Hondas have unique specs for rear diffs or transfer cases As always, go by your own vehicle specs first.
Just be careful of the 100c cst test of the oil you are considering. About 20 years ago SAE lowered that figure for 75w-90 into 75w-80 territory for fuel economy which inspired some oil makers to produce 75w-110. So see what your manufacturers recommends for 100c cst. During the last drain/fill all my vehicles got SuperTech synthetic 75w-140 which had great 40c and 100c specs.
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I use Amsoil 75w90 in my Tacoma with 4.88 gears. No complaints.
I know there’s tons of gear oils out there and there are many sales pitches and technical specifications that seem to be distinguishing features. That said, I’m also aware of the objective evidence that just about any major name brand will serve 99% of the people just fine as long as the gear oil is changed occasionally and kept free from water intrusion.
I also believe, as @dnewton3 has shared many times, you almost certainly cannot go wrong picking a gear oil that carries the J2360 certification. Those listed on the QPL have undergone serious testing and will perform well in just about any situation we will require on a daily basis. Some very good gear oils are not on the list because of the extensive cost of some of the test requirements.
I also believe, as @dnewton3 has shared many times, you almost certainly cannot go wrong picking a gear oil that carries the J2360 certification. Those listed on the QPL have undergone serious testing and will perform well in just about any situation we will require on a daily basis. Some very good gear oils are not on the list because of the extensive cost of some of the test requirements.
I’ve done Valvoline FS, Motul 300, Delvac, Mobilube PTX 75w90 for 911 transaxle, and iirc Fuchs Titan Syntopoid (Merc C350) over various vehicles. Usually in 75w90. Would use Mobil 1, Amsoil SVG w/o hesitation. Will be posting UOA of 40k runs of Motul from front and rear diff of GX460 soon from Cat labs.
GX460 transfer case just got Redline MT-LV 70/75w. I posted a VOA on it a while back - strong add pack and met Toyota/Lexus 75w reqt.
GX460 transfer case just got Redline MT-LV 70/75w. I posted a VOA on it a while back - strong add pack and met Toyota/Lexus 75w reqt.
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MolaKule
Staff member
If you mean "Oil Properties," I can think of 3:
Viscosity
Additive Package
Specific Application
One uses so little diff fluid and it does not get changed very often so why not use one of the best being Amsoil SVG?
So I am a fan of Amsoil gear & ATF but for motor oil I use Rotella T6 5W40 for my PSD.
So I am a fan of Amsoil gear & ATF but for motor oil I use Rotella T6 5W40 for my PSD.
Specs from manufacturer first, then selection second. I know nobody sells a replacement transfer case fluid for my ATS's... so I have to use the super special AC Delco elixir. There are also rumors that their gear oil has additional specifications related to heat, but I can't recall where I read that.
I also noticed some gear oils have considerably less viscosity than others in the 75w90 world, so take that for what it's worth.
I've run only AC Delco driveline fluids in both my ATS's. But I do have Valvoline 75w90 on the shelf cause that GM fluid is $$!
I also noticed some gear oils have considerably less viscosity than others in the 75w90 world, so take that for what it's worth.
I've run only AC Delco driveline fluids in both my ATS's. But I do have Valvoline 75w90 on the shelf cause that GM fluid is $$!