Hi All,
Did a search and google but could not find a reliable answer partially due to needing a technicality cleared up once and for all.

I'm getting a service done tomorrow and would like to know what grade of diff oil is suitable for such differentials. My guess from what I have read is 80w-90 or 85w-90. The TRD FR oil would be perfect but hard to get hold of at such short notice.

As far as I know these figures indicate low and high pour points, so is it unwise to fill a diff which recommends 85w-90 with 80w-90? as to me this indicated a larger temperature zone under which the oil most effectively lubricates.

Relevant Points to this issue:
-The TRD diff in questionis a 2-way selectable LSD setup, currently setup as a 2way.
-The 2jz prescribed 10w-30 engine oil, instead i'm running 5w-60 Castrol Edge as recommended during servicing. Hence I expect that 80w-90 would be better than 85w-90? How about 70w-140
- Oil changes are recommended for the diff every 5Ks
- Only motul product matching is the http://www.motul.com.au/product_line_up/gear_box/gear07.html
- Not trying to cut corners here, the 2way is one of my favourite parts of the car, feels great under power and off when sliding maintains excellent feel.

Thanks

I am unsure of what the difference would be essentially between the 80W-90 & 85W-90 hopefully Kurt can clarify this. As they say oils aint oils but I dare say you would be right with a 80W-90.

Im curious as to where you got your info from which states you should change your diff every 5000kays?

I must admit that's a bit odd! If you track your car a lot and the diff is exposed to prolong use @ extreme temps, yeah maybe but in a street car that seems over the top (but hey it's better to change a fluid too soon then too late!)

As per Indy using the Castrol Edge 5W-60 over the prescribed oem recommendation of 10W-30 is because the Edge is a full synthetic based oil vs the oem mineral oil.

Basically it's chalk and cheese between the two fluids, with the synthetic being thinner at startup temps (free flowing) and being able to withstand a lot more thermal stress under high load conditions due to the synthetic polymers (which displays superior shear stress properties)

So basically the castrol synthetic is thinner at startup and can withstand more thermal stress under highloads equals win win vs the 10W30.

Well I'm inheriting it from Brian's regime, which would make sense to continue as once the cycle is broken it will be less effective to jump back into it. Mostly this (5k changes) is heard on drift/circuit sites as these guys run 2ways, many of which are "dailys" too. A normal car would be having the oil changed every 30Ks.

I guess that a mechanical/clutch type lsd will be working harder than a standard lsd, because the differential will spend more time transmitting a greater variance of torque to either wheel, opposed to an LSD which would do so more on acceleration in a shorter band that the previous... I stand to be corrected as that statement is based on newbie knowledge.

have a look on the trd website, sorry replying from my phone and can't find out for you but from memory its 85w140

i only trd genuine trd oil in my trd diff, its not too expensive and your local dealership should be able to get them

http://www.trdparts.jp/english/parts_lsd-oil.html
aha found it finally 85w-140, got to google TRD LSD oil not diff or differential oil..
If I can get it, I'll use it, otherwise at-least the required index is known now.

lol was close. From memory its about 50 a litre, normally a litre should be enough aswell

TRD oil is a bit of a wank IMO.

A generic Castrol/Valvoline etc of the same grade will be half the price and perform just as good.

After all TRD do not manufacture oil, just source it through someone like castrol etc.

Personally I would recommend a mineral LSX 85/W140 ..from any reputable manufacturer.. if you experience any limited slip chatter/shudder add some LSD Friction modifier to the oil.. best Friction modifier we have found is to be the Torco type F and strangely enough Ford motorsport! :)

The above is what we use in all mechanical LSD applications :)

I think you'd be hard pressed to find a mineral 85W140. All that I've seen are fully synthetic. I'm running Castrol SAF-XA 85W140 in my factory LSD. It has a friction modifier in it already, which takes the GL rating upto a 6. I noted atfer I'd installed it Toyota recommends a GL5 which I have since found in the form of Mobil1 SHC1D 85W140 but it only comes in a 4L pack here in NZ. I supply both these to our workshop (Ford & Mazda dealership).

Personally I wouldn't use mineral oil in my diff or gear box due to the long service intervals(80,000km) & high stress loads placed on them(with spirited driving). Fully synthetic FTW!

I have a couple of 44 gallon drums of VP Racing LSX 85/W140 here in the shop ;)

Generally speaking full synthetics are not recommended in mechanical Limited slips either. :)

From KAAZ site

Oil for Kaaz L.S.D. DO NOT USE SYNTHETIC BASE OIL ON KAAZ LSD.

It is important to use 80W/90 GL-5 specification gear oil on Kaaz LSD. We highly recommend using our own Kaaz LSD fluid. DO NOT USE SYNTHETIC BASE OIL ON KAAZ LSD. Kaaz LSD may not function smoothly.
--------------------------------------------------------------------------------


L.S.D Oil Change

When one has a Kaaz LSD, it is important to do routine maintenance of LSD Oil. We recommend to change LSD oil every 5000 miles for daily driven and occassional track use vehicles. If the vehicle is full race,we recommend more frequent oil change.

Well on that basis I'd go with the TRD 85W140 oil in the TRD LSD then.

8000km service intervals for street use would be a bit of an overkill wouldn't it? Almost makes them impractical. I'd rather have a standard LSD than have to do that a couple of times a year, especially if you dont have access to a hoist.

Meh.,.. I give up... what would I know.. :lol:

everything I have read suggests that using anything other than the Toyota/TRD LSD oil gives a notchy noise and inconsistant lockups...

it's no dearer than any other lsd oil, so I'd use it over the others.

Cheers for all the input guys.. really helps to hear both sides, when ur trying to establish an opinon about this kind of stuff.

I kinda ran out of cash ahahaha on the last stint, so this didn't end up happening, but will happen in 5000kms, in that much time i'll be able to tell if the diff's performance has worsened, without anything detrimental happening.

Either way I think i'll do the changes every 5000kms or so with the oil, not that money is no object, just don't want something simple like this causing problems (read have other issues to deal with hahah)

Noise is no issue, don't really mind it. Can hear it locking rumbling a fair bit, will have to take a proper video soon to demonstrate.

http://my.is/forums/f88/trd-lsd-oil-use-167000/ last post

As for mineral vs synth... the general consensus across the inter webs is TRD differentials should use a mineral based oil with friction modifier...
to be noted is that TRD LSD oil already includes such a friction modifier.

Thanks hey

I use Redline shockproof gear oil in my TRD mechanical LSD. Costs a bomb, but it is the shit!

It is rated for a range of viscosities, which include the reccomended from trd.

Diff is PERFECT with this oil in it, perfect combination of lsd action and smoothness for every day driving.

REDLINE OILS FTW!