80w-90 in the rear diff

I've got a 2014 sr5 4.6L 4WD. Long story short my pinion seal on the rear diff is leaking and throwing oil all over. I wanna keep it full of oil for as cheap as possible until I can get the seal replaced in a week or two and Walmart has a deal on 2 quarts of 80w-90 for $10 right now. Will it be safe or should I spend the extra on the correct oil?

 

You'll be fine with 80/90. Won't hurt a thing. Any idea why the pinion seal is leaking?

 

Have you checked your breather cap to make sure it freely spins and isn't plugged up?

 

My best guess is it just wore out over the years, I don't think the bearing or yoke is worn out because I'd imagine the driveshaft would be wobbling but it's still firmly in place. It's been in the northeast it's entire life but it's only got 160000 miles on it so I don't think any of the metal parts would wear out that soon unless the previous owners used it for some serious hauling

 

I didn't even know the rear differential had one honeslty

 

80w90 is fine. I ran that for a while since I had and Auburn Limited Slip and that’s what they spec. No issues except it felt like driving through zero slump concrete in the winter.

Like @KNABORES said, you may have a clogged vent; it’s circled in the picture. That can cause the seal to weep when the axle gets hot. But it may well be the seal if the leak is profound.

 

Thank you, do I just hit that with some brake cleaner and a shop towel from the outside?

 

My 2020 did the same thing, a bunch of mud dobbers built a nest on the breather, i replaced the beater and the leak went away.

 

You can unscrew it easy enough - maybe a 14mm wrench? Then try blowing through it from the inside like a PCV valve. A couple of doses of brake cleaner might free it up if it’s stuck, otherwise I think they are $10 or $15 dollars at Toyota, maybe cheaper at the parts store.

Some guys replace it with a nipple and some fuel line run up to the tail light, then turn the hose downward to keep moisture and dirt out. I think there’s a DIY thread here title something like Rear Diff Extended Breather Mod or some such. Personally, I just replaced mine a year or two ago with a factory part. I don’t ford deep water, but we see all five seasons and I’ve had snow packed up everywhere in the frame from snowstorms.

 

Interesting
Is the design the same on a 2021 4x4?
I have a very very slow seep on my rear diff, symetrical though(in between each Bolt)

 

Yes - same axle housing from 2007-2021.

Are you getting a drop of oil on the ground? Or just seeing evidence of seepage? The factory uses a fiber gasket between the third member and housing (where I’m assuming you are seeing the seepage) that can saturate and seep, but not drip. It won’t cause an appreciable loss of oil between oil changes - assuming you are following good service intervals and aren’t pushing diff oil to 100k miles.

My ‘13 had some evidence of seepage on the gasket between bolts but never dripped a single drop, and was never low on oil. I had a limited slip installed at 80k miles and they siliconed the flanges instead of using the paper gasket.

Maybe post a pic, but unless it’s dripping, I wouldn’t be concerned.

 

@ 160k miles I would just replace the breather I did mine recently during a rear differential oil change the truck has 270k miles with the original rear differential breather it was in good shape but like the PCV valve it’s a cheap part and could prevent bigger problems.

there is a mod where you can relocate the breather to the driver side rear taillight which can be handy if you off road

 

Easy mod. Oh. And chicks dig a looooooooooong hose!

 

Never a drip, just a pattern that is fairly uniform between the bolts
Minimal loss
My Warranty is voided or I would maybe have it replaced.

Tranny shop said they could silicone it and it won't ever leak again, might just do that

33K miles, saw the seep first time at around 20K. Was rear ended and slightly bent frame at 15K(might have nothing to do with it).