Differential oil - keep or change?

Coming on 10000 on my taco soon. Will do my own maintenance and wonder if I should keep or replace the diff oil with AMSoil this.
https://www.amsoil.com/shop/by-product/gear-lube/severe-gear-75w-90/?code=SVGQT-EA

 

I would leave it alone for 30K unless the way you use your truck calls for something better than the standard dino oil (like racing or heavy off roading).

To me it's just wasted $$$$. But that's my $0.02

 

I changed mine over to Amsoil at 40k.

 

The OEM fluid is synthetic not dino. I changed mine at 17,000. I am going to wait until 25k to do the transfer case and 30k for the front diff. The fluid was about $100 about $20 more than Amsoil since the Toyota fluid is sold it liters and everything else is sold in quarts. I also replaced the crush washers/gaskets for $5.

The fluid was black but that doesn't mean anything. The magnet had a decent layer of very fine metal particles. It is possible changing it early helps prolong the diff life by removing those abrasive particles. It really depends on if $100 is a lot of money to you. If it isn't it is pretty cheap insurance and it's an easy job to do yourself.

 

The magnet holds the particles so they rest of the differential doesn't see them. They can't hurt anything if they are stuck on a magnet.

10k rear diff oil change is a bit early unless you submerge the rear axle over the hubs often.

 

If you don't care about the cash or time it takes, I say go for it.

For me it was relatively cheap piece of mind (https://www.tacomaworld.com/threads...-manual-transmission-6mt-fluid-change.481719/) Toyota didn't have their shit together for the early runs of these trucks but I think it got better.

OA

 

I went with Mobil1 for F&R dif's at 30K. I will do the rear dif again in 30K intervals. The front dif I'm going to wait something like 60K intervals.

 

I might just for the peace of mind. I spend close of $100 a week for smokes...why not for gear oil?
How many quarts I need for the rear diff?

 

3 plus a little, get 4

 

May as well change your oil every 500 miles while you are at it.

 

in a perfect world i would agree with this. but the imperfect world of the 3rd gen fluids had me concerned. so i changed the diff to Amsoil. big deal?

not really, but what was revealed is that my diff was about 300ml low from the factory. this was around 14k.

luckily I've had no diff issues. currently 24k

 

Feel any difference from OEM oil to AMSoil in diff?

 

i changed all the fluids that visit before getting on the road for a 2 week trip to CO. there was change yes maybe or maybe not from the diff, but i changed MT oil as well, so I'd say it's hard to tell exactly if or how the diff changed... i wasn't having any symptoms before. but the MT was a little smoother especially going into 3rd. used Royal Purple on the MT.

 

I've always changed diff oils in my toyota's at 30k-40k range. If you dont offroad or tow much, i kinda feel like its pointless to do it before then, but to each their own. And i always used Mobil1 products. Never had an issue.

 

Different amounts for different diffs, but this is wrong. He should need 4.0 or 4.2 (depending on whether or not he’s driving a stick). I’d get 5 quarts.

Not sure that this comment adds anything. Multiple people here have had rough diff fluid and plug magnets caked with shit before 10k and even low levels of fluid. OP wants to look after his truck. There’s nothing wrong with that.

I definitely noticed a difference (mostly in smoothness) but it’s hard to tell why since the OEM fluid for me was in rough shape and likely underfilled from factory. All my research has shown that Amsoil is pretty much as good as it gets as far as performance and change intervals are concerned.

OA

 

Two things I considered...

New gears produce a lot of heat. Heat breaks down fluid.
Thus, every gear manufacturers recommendation for proper break-in and 500 mile fluid change.

Or...

Is Toyota 75w85 some kind of super lube, the gears REM, had some kind of factory break-in and/or came filled to the proper level?

 

Mine was 1 quart 8 ounces low from factory.
No leaks and no problems with it other than that.

 

My rear diff had no oil from the factory and detonated w/less than 500 miles on the clock. Got a new one, my 1st payment refunded and 7yr 100K platinum warranty. Been thinking about changing it soon though.

 

My front dif was only 7 ounces low.
Transfer case was full.

Perhaps the assembly line was moving too fast for the one worker to keep up with 3 jobs.

Job #1- Fill transfer case.
Job#2- Fill front differential.
Job#3- Truck has already moved to next location on assembly line.
Oh well...

 

I changed my rear diff fluid over to amsoil at 10k. The drain magnet was covered in sludge.