If you have the factory viscous LSD, the LSD operation is not influenced by the oil, so its not as critical.
 
In my previous SW20, I had a plate LSD and went through a few redline oils all of which caused the LSD plates to chatter in one way or another.
 
I ended up using a synthetic Mobil oil, sorry cant recall the grade/type, but it solved the LSD chatter and the shifts were still great.  It was what Tony Flood recommended at the time.
 
Cheers 

whats the difference with gl4 and a gl5?

http://mr2.noegruts.com/trannyoil/trannyoil.htm
found an interesting link about this

You can buy it direct from caltex in I think welshpool. I bought a 20l drum of it for approx $180, but they should do the smaller containers, of which you will need 2.

I got the Penrite gearbox oil. You have to make sure you get the right one with Penrite, as there are 2 types that appear the same, but are not. I had to get 2 x 2L bottle. But I'd say the gearbox uses around 2.5l or so. The BGB has the exact volume required.

TIPSIDUECE

whats the difference with gl4 and a gl5?

 
The GL (gear lube) rating refers to EP (extreme pressure) protection. The higher the number, the more additives the oil will contain.
Check out:
http://www.widman.biz/uploads/Transaxle_oil.pdf 
 

Interesting with the S54 with OEM LSD started with an unknown oil put in by mechanic, ran for 1000 kms and put Red Line MT-90 No issue and was actually better. Ran for 4 k then swapped to lightweight shock proof and it was crap swapped it out immediately. Waste of money.
In the E153 everyone swears by it , but ill never us it again.
Ill have to make the decision soon for my new E153 but im torn b/w the MT-90 and just the Caltex what Toyota uses

BTW here are the capacities according to the manual:
S54  2.6 liters
E153  4.2 liters

4.2 liters wow!

S54 
E153
 
....how do I tell which one I have? (although I am pretty sure I asked this years ago, and I worked out I have the non-LSD, which I assume is the S54?)