Can I use 80w90 in my diffs/tcase?

Can I use this stuff in my t case and diffs?

thanks.

 

RTM

 

The manual calls for Toyota brand 75w85 which I don’t have access to here.

that’s why I’m asking.

 

Here is a link where many discuss this, I bit the bullet and put factory Toyota oil in my transfer case...not cheap! I put 80-90w Lucas oil in front and rear diffs.

3rd Gen DIY maintenance quick reference | Tacoma World

Edit: Another one!
Differential and Transfer Case Fluids | Tacoma World

 

Thank you! I’ll check all this out.

 

You want an LV fluid in the tcase, like this or the more expensive Toyota version.

https://www.redlineoil.com/mt-lv-70w75w

 

ECGS recommends going to a 75w-140 in the diffs. TCase is Toyota only fluid if I recall. Heres the link for ECGS article Toyota specific but they have other good ones about hypoid gears in general. These guys are the experts when it comes to gears.

https://eastcoastgearsupply.com/files/PDF Files/toyota-clamshell-bushing-faq.pdf

 

Don’t use that in the transfer case. It will make it hard to engage in cold weather. You need the Toyota LF (low friction) fluid in there that is called for in the manual. I found that out the hard way.

 

thanks. I’m in the Middle East so it doesn’t really get that cold here. Is it still fine to use? I put it in two months ago and I’ve had no problems so far.

 

I had no problems with 75/90 in my T-case until it was very cold. I don’t think you’ll have an issue, other than maybe slightly worse MPGs. But yeah......you want the special thin oil in there when in cold winter conditions.

 

I used ravenol, fwiw.

 

You can but when its cold out the 4wd might not work. Something like purple syncromesh or the lightweight ford/bmw manual transmission oil would be better.

Also fwiw the 75w85 type gear oils have viscosity similar to 30w motor oils. So if you live in the frozen north in your truck won’t four-wheel-drive I suppose you could try some 5W 30 in there instead of whatever 90w gear oil you used.

 

I ran syncromesh for a bit. Seemed to hesitate more in colder weather. The ravenol I switched to seems better.

 

Any idea why ECGS recommends this? I've seen the recommendation a few times but not completely sure why. I did the ECGS bushing on the weekend and went with Redline 75W85 GL-5. My truck is new and under warranty. My concern is if something went wrong I don't see telling Toyota "Because ECGS said so" as a good reason for going with something other than Toyota specified.

 

If it’s the front differential maybe it’s because they are assuming you replace the needle bearing with their bushing.

 

When I test drove a brand new one it was hesitant to. I think their four-wheel-drive shifting system just kind of sucks. You’ve got to be moving and wiggle the steering wheel a bit to get it to engage.

 

Believe me. I’ve been down this road and know all the ins and outs of the transfer case. When it’s -15C, and you got the 75/90 in there, it ain’t shifting until the exhaust warms it up, which sucks if you are stuck in the overnight snow and need to shift into 4WD to get out.

Once I switched back to the Toyota Low Friction fluid. No problems at all. Just the typical massaging it needs on any given day (unloaded, in neutral)

 

Agreed

 

I did but fail to see what difference that would make in what oil to use. No change to the diff itself.

 

Probably because ECGS partners with Lucas.

Even Redline seems to troll them with their own 80W140 gear oil, " An old-school viscosity that still out-protects the competition." On the ECGS site they say that synthetics don't have the high heat protection of a traditional dino gear oil. A lot of conjecture and they even say so in their own words, "An easy not so scientific test..."

I'll stick with the Redline white paper on their gear fluids:

The enhanced lubricity and better heat transfer capability of the synthetics enables Red Line Gear Oils to reduce axle temperatures to insure a thicker oil film in the contact zone and provide better equipment durability. Red Line Gear Oils will reduce differential temperatures between 10 - 70°F and transmission temperatures between 10 - 50°F. The actual degree of temperature reduction depends on the speed and load conditions of the equipment - with more stressful conditions showing greater differences. Even greater temperature reductions can be seen when comparing axle break-in temperatures. The friction modifiers allow a more gradual wearing in of mating surfaces, significantly reducing break-in temperatures and minimizing potential problems associated with a loss of hardness of the gear tooth surfaces.