Redline lightweight shockproof 75W90 in my gearbox?

[AgtX]

After reading a load of gearbox threads...I fancy using Redline lightweight shockproof 75W90 for my gearbox, its been recommended here & in the "useful threads" section but also some have said its a GL5 oil & it will eat the various brass parts of the gearbox internals, is this true? What oil is best?!?!

Thanks

 

[spoonman]

We all use it dude, and a number of gearbox places recommend it.
You would wear out your gearbox through use or break it from overload stress before anything gets eaten.

while you are buying smurf blood (Red Line Lightweight Shock Proof) get some heavy weight shock proof and put that in your diff

 

[Auss15]

AS he said why would they make an oil that would eat your gearbox....

 

[AgtX]

no, Im saying from what I read, GL5 oil is not suitable for a gearbox that required GL4 oil, I assume gearboxes that take GL5 oil have no brass

"GL-5 is not necessarily backward-compatible in synchro-mesh transmissions which are designed for a GL-4 oil: GL-5 has a lower coefficient of friction due to the higher concentration of EP additives over GL-4, and thus synchros can not engage as effectively. Also, transmissions which explicitly call for GL-4 oil may have been designed around this lower concentration of EP additives and thus may contain yellow metal parts which GL-5 will corrode"

 

[seal123]

Bringing this thread back to light can anyone provide any more information on which gear box oil is best? I'm stuck between the shock proof and red line MT 90 GL4. Also i've read and heard overfilling is best which i have always done anyway but how much does the S15 take from this, i'm guessing x3 1 us quarts measures? Or can i get away with 2?

 

[Cap'n Crash]

I camy answer your first question as I don't use redline fluids. However I know when people are overfilling their gearboxes their putting in two litres, a US quart isn't quite a litre so you'll need 2 full bottles plus a bit of a third.