Rear Differential Fluid after Gear Change

[stokers]

Just changed my gears and installed an ARB locker. What fluid do you recommend I use? Should I plan to change fluid after a break in period? If so, after how many miles and should I use same fluid or something different after break in period if needed. Please let me know you think.

Thanks
Bob

 

[bronconut73]

Everybody makes great synthetic gear oil now. So you could prolly pick any bodies synthetic and be good.

With the 9" being a bitch to drain I would use top notch stuff, to hopefully extend lube changes. You'll need to drain at 500 miles(?) after a gear change any way right?

Something to consider.

If you use Royal Purple for example, and you get a leak you'll know if its your axles or not because its purple lube.
Unless you already use that in your engine or transfer case, haha....

 

[73azbronco]

Also with ARB, make sure you are using a lube not containing additives for limited slip.

 

[blubuckaroo]

Just use a good GL-5 75W-90. If all you can find is the LS type, it doesn`t matter. It will still work fine in your non-posi locker.
I haven't heard of changing gear oil after break-in, but I do like to do scheduled oil changes and always change gear oil after running in deep water.
Synthetic sounds like a good idea, but only if you run at extreme temperatures.

 

[bronconut73]

Most gear manufacturers and differential manufacturers want you to change fluid after a 500 mile break in. I presume its to get that initial break in wear metal out of there before the lubrication "long haul" change.
Other than going to Super Cel this year I would likely struggle to put 500 miles on my eb in a year, haha.
So yearly or after water crossings would cover my gear lube change interval requirements as well.

 

[Nevadasmith]

What I do on the 9" after a gear change (with out limited slip , air locker is fine) is coat the ring gear in an ngli 2 grease that contains an EP aditive, then fill with syn 75w140 and skip the break in oil change. Change oil yearly, or after water crossings, I have had great success with this method. And my personal preference on oil is Lucus oil, but I don't know that it is any better than anything else.