Rear Diff oil, Synthetic or conventional?

Is there a consensus on using synthetic over conventional rear diff oil? Its nearly twice as much. Getting ready for 1st change in my 2019.

 

I would use synthetic, why risk using a lesser quality oil? The price of a new differential is expensive

 

Synthetic all day

 

ECGS says the opposite.
https://eastcoastgearsupply.com/ft-2536-ecgs-gear-oil-recommendation.html

 

When I see synthetic gear oil on sale I buy it to have on my shelf. I always change fluids sooner than later.

 

Use syn if you work the diff hard or you're willing to double your OCI in normal use

If you are a low stress driver, dino and recommended OCIs are just fine

 

Use Valvoline synthetic

$29 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90 flexfill pouches. $15/qt. You'll thank me later.

 

I don’t ever use synthetic. My diffs have not blown. The gear companies tend to suggest thicker conventional oil so that is what I use.

Not on the Tacoma, but on other vehicles (with Dana 44 rears especially), I have definitely had pesky pinion and axle seal leaks that would just not stop with synthetic (even with new seals), and as soon as I went back to conventional, they would stop. Maybe the conventional stuff conditioned the seals a bit better, I don’t know. Issues like that are mostly unheard of on Tacomas so it doesn’t matter that much, but I still run conventional just because.

 

I'm sure conventional would be fine but synthetic is a superior lube. Synthetic will cling to the metal along with kind of ball up under pressure acting like a little bearing on the surface whereas conventional will just squeeze out unless you go thick enough.

Typically gear oil isn't changed often (if at all) so unless you water cross often and end up changing your gear oil like once a month, I would just take the hit in price and run synthetic.

I don't believe in doing this but tbh many people run a gear lube from factory until the vehicle is in the scrapyard with no issues so in my opinion if you're gonna change it, may aswell use a quality synthetic

 

Don't be a square, use synthetic. Set it & forget it

 

Synthetic just get

$29 75w 90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w 90 at your local auto parts store no need for fancy Toyota oem fluids … even dealer uses the 75w 90 full synthetic made by valvoline …but If u want to splurge a little I went with amsoil 75w 90 full synthetic.

 

I’ve used Redline synthetic gear oils in my 1st, 2nd, and 3rd Gen Tacomas over the years. No issues.

Always good info from ECGS.

 

This is the way. Advanced only had 2 squeeze pouches and one larger bottle, holy shit are the squeeze pouches easier. Would have saved myself lots of swearing if I'd went someplace else and only gotten the pouches.

 

Could have poured the bottle into one of the empty bag.

 

I put Super tech 75w90 synthetic in mine a few months ago

 

East coast gear supply has written a extensive article and done a ton of research on the topic all they do is GEARS and diffs I 100 percent trust there advise. to sum it up if you use conventional they spec a lucas gear oil i forget the weight the article is specific and the ams oil is second not because of quality but they didnt see much benefit over lucas for the additional cost

 

I was actually looking for that brand when I bought synthetic engine oil. They have it back in stock now, thanks for the reminder.

 

I could never find it or enough for the front and rear at my local Walmart. What I did was order 6 quarts for curbside pick up because online they said it was in stock. When they went to fill the order they then offered to ship it to me for free when they didn't have enough to fill the order. at about $10 a quart it was a deal.

 

Redline 75w140 in anything I've owned over the years, I'm 41 now, and started using it when i was 18... though working in shops in my late teens early 20's access to stuff like that probably is why my hard use things have lasted and always seem to be a solid shape.