I'm upgrading my rear diff cover so I need to buy some gear oil. I have been reading through the forum and have decided I will go with a non-synthetic oil. Just wanting some recommendations on what weight to get I don't tow but I live in Colorado so the winter temps can get very cold. Secondly I was wondering what the preferred brand for gear oil people like.
What gear lube Rubicon Dana 44 with stock lockers?
- Thread starter Dahbarez
- Start date
GL-5 is the important spec , and you will see the weights on the lubricants specifications thread under commonly asked questions.
A heavier is recommended for the back , as it is loaded more often in terms of drive stress, but I can't remember the numbers and I'm not going to guess.
A heavier is recommended for the back , as it is loaded more often in terms of drive stress, but I can't remember the numbers and I'm not going to guess.
I run conventional 85W-140 GL-5 in mine though the exact viscosity is not critical. Valvoline, Castrol, Torco, Mobil, NAPA, etc. would all be fine. No additives are needed.
Have you had any experience with lucas gear oil that was the one I was leaning toward as I am a big fan of lucas oil products https://lucasoil.com/products/gear-oil/gear-oil/lucas-heavy-duty-85w-140-gear-oil
I'm not a fan of Lucas (overpriced IMHO) or any synthetic gear lube for that matter for our axles.
The factory calls for 75w-140 synthetic.
I've been running Valvoline Synpower 75w-140 for ten years.
I've been running Valvoline Synpower 75w-140 for ten years.
rouxbicon
TJ Enthusiast
I run the cheapest conventional 85W-140 GL-5 I can find. Guy that did my gears said the brand doesn't matter and the cheap stuff works just as well.
Tis one week from deer season, I've been trolling the bow hunting forum and getting my deer stuff in-line. Plus, I haven't really been tinkering with my Jeep, just cruising and enjoying it...for once, I've not searched for something "broken".
I actually passed through your neck of the woods last week on the way to Destin FL. We stopped at the rocket rest station at the border for my son to pee.
Jeep is almost ready, I still have a few things I'd like to get to but I've been way too busy to do anything. Putting house on market, finishing little things I've put off and just life in general. I have a short list of Jeep projects but they can wait until life slows down.
He will remember that rocket all his life.
It's hard to believe us rednecks put man on the moon... Houston them boys have done got into the freeze dried chili and they're tore up bad...
And that's fine for a factory axle running the factory installed gears. It's when new aftermarket gears have been installed that need to be broken in when it's best you don't run a synthetic gear lube. Or when you're running aftermarket axles like from Currie where their warranty requires the use of a non-synthetic gear lube. Why? It was surprisingly found during difficult tests that the gears run cooler when lubed with a conventional than with a synthetic which was found to hold the heat in the gears. Why were the tests conducted? They were having higher than expected aftermarket R&P (factory gears are pre-lapped before installing) gear failures and it was finally tracked down to the increasing use of synthetic gear lubes. True.
Which is why more and more aftermarket providers like Currie, Revolution Gear, and others are requiring conventional gear lubes.
For example, this is from Revolution Gear at https://www.revolutiongear.com/ring_and_pinion_break_procedure
"Recommended gear oil is an 85-140W, Non-Synthetic, GL5 grade or Higher, Name Brand Oil.
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What is recommended when you change a diff cover on a factory axle running the factory installed lockers?
I have been a Valvoline fan for years. Their refining and additive package have been top shelf for decades.
In my youth I was told Pennzoil was the best. That may have been true when they (and Quaker State) sourced their oil from Pennsylvania (thus their names) because the crude oil in that area was superior to anything else pumped out of the ground. But those wells have been dry, or nearly so for a while. And they stay competitive through marketing, not science. Had a Pennzoil rep tell me that himself. Perhaps they have improved, but Valvoline and Mobil seem to do more science to their products than others do.
I think most boutique brands (like Lucas) came up with 1 or 2 products that work well, but when they expanded to a complete fluid company most of their products are "improved" by food coloring. No better than many, though better than some.
In my youth I was told Pennzoil was the best. That may have been true when they (and Quaker State) sourced their oil from Pennsylvania (thus their names) because the crude oil in that area was superior to anything else pumped out of the ground. But those wells have been dry, or nearly so for a while. And they stay competitive through marketing, not science. Had a Pennzoil rep tell me that himself. Perhaps they have improved, but Valvoline and Mobil seem to do more science to their products than others do.
I think most boutique brands (like Lucas) came up with 1 or 2 products that work well, but when they expanded to a complete fluid company most of their products are "improved" by food coloring. No better than many, though better than some.
derekmac
TJ Addict
WranglerAngel05
New Member
Does anyone have any suggestions on whether running a conventional gear oil would require more frequent changes? I know synthetic is touted to "last longer" but wanted to make sure the same applies to the gear oil versus standard motor oil in regards to frequency of changes.
The service interval for the axles won't change for synthetic or conventional gear oil. (The Factory Service Manual doesn't list different mileages for applications calling for synthetic gear oil vs. conventional gear oil.) That doesn't mean that you can't leave synthetic gear oil in the axle assemblies longer than conventional gear oil, only that the industry literature doesn't encourage longer service intervals with synthetic gear oil as it does with synthetic engine oil.
I generally stick with a 30,000 mile service interval for differentials unless there are frequent water crossings or other events that suggest a more frequent interval.
I generally stick with a 30,000 mile service interval for differentials unless there are frequent water crossings or other events that suggest a more frequent interval.