5 quarts in rear diff of '23 TRD OR?

I just changed fuild in the rear diff of my '23 TRD OR and was expecting to add 4.2qts to fill it to the bottom of the fill plug. It took nearly 5 qts and I didn't spill any. Is it supposed to be 4.2 qts or filled to the bottom of the fill plug?

 

^Inspection standard is within 5mm of the fill port level. Since the oil is in the whole length of the axle housing, 5mm tolerance in level accounts for a lot of volume.

 

Whoa. Quarts?

 

I got in about 4.75L. Part of it is because, as explained above, the spec is actually to 5mm below the hole. Although filling to the hole won’t hurt anything.

 

Yep, five 1 qt bottle are empty. I can drain out and catch half a qt or so which would get it closer to the 4.2qts. I've read where overfilling isn't good.

 

^Not needed. The inspection standard is by level, as volume can vary with axle mfg tolerances. Overfilling (which you aren't doing) doesn't hurt anything either, as lubrication depends on an oil slinger in the diff whipping up oil as the diff turns. There's no pump to cavitate.

 

Truly overfilling isn’t good, but you’re not doing that by going to the hole. It won’t matter.

 

5 quarts sounds right, my buddy (a tech) was surprised how much it took, he had to rob some from his neighbor to finish filling.

 

It doesn't surprise me... I did both diff's and the TC about a month ago. First time since I bought it new. I remember thinking 'Wow. is the rear diff ever going to fill up?'... Mine took a bit over 4.5... But I didn't worry about it, I just slept better knowing it was filled up to the fill plug.

 

Thanks guys. I appreciate the numerous responses.

 

Mine took 4.0 qt

 

My exact sentiments when I did mine recently.

 

are you sure your truck was level when you filled this or was the rear higher than the front?

 

Same thing here. Did a change at 31K miles and it took just under 5 of the squeeze bags of Valvoline on a level surface. Had to make another run to get enough for the front diff.
I changed at 15K as well because I tow, had the same issue, but thought it was because I spilled a bit.

 

Also, I thought I saw somewhere that the OR / E-Locker diff takes more oil than a diff without the locker.

 

Ah, I forgot about that. I actually did have the rear jacked up some to make it easier to fill. But the wheels were on level ground.

 

That could have thrown it off a bit

 

I'll pull the fill plug tomorrow and see if anything comes out. I'm doing the front diff tomorrow.

 

Not to turn this into another lube thread, but it sounds like a lot of folks use the Valvoline squeeze packs (

$28 75W-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75W-90). The Toyota shit is ludicrous expensive and V seems rated fairly highly. Also cheaper, so looking at doing my front/rear in a few months at 15K. I know that's early, but I've had crazy experiences on other trucks with lumpy/crazy looking diff juice on regular interval drains.

My 2012 GMC Sierra 5.3 CC 4WD with 115K on it has had it flushed a few times now, since the first time I did the front at around 30K it just about freaked me out (DARK...almost lumpy). Found out the wife had been driving the thing in AUTO 4WD quite a bit and that's not good....in good weather. Big piece of tape over the knob now with "LEAVE IN 2WD unless you're knee deep in snow".

By the way, that Sierra is the best vehicle I've ever owned. 5K mile oil changes, tires and brake pads. Plugs and dropped the pan at 100K (CLEAN) A rear wheel speed sensor went out a few years ago, that's it. $20 part from Amazon and 15 minutes....fixed. Looks and runs like new. I've had a "RANGE" device plugged into the ODB port and have had it there since the truck had around 10K miles on it so it never runs in 4 cyl mode. I think that might have something to do with why I'm not seeing rod problems.

 

I agree, and here’s a thought to ponder. If you go to a driveline shop and you get a new set of gears installed; they will tell you to change the diff fluid after a break in period of about 350-500 miles.

With that being said , there quite a few threads and some dealer information about whining rear differential gears. I changed my differential at 450 miles. I have just over 18,000 and there’s zero noise coming from the rear diff.

just something to think about…..