Why 75W-85 GL-4 gear oil so hard to find/expensive?

[GunsMadeAmericaFree]

My son has a 2000 Chevy Metro, (manual transmission) which needs the front axles replaced. As part of that procedure, they need to also replace the transmission fluid/gear oil. Both the dealership where my son has started working part time, and the car's owner's manual say we should use SAE 75W-85 GL-4 gear oil. I have searched far and wide, and most of what I find is 75W-90 gear oil that is GL-5, not the GL-4 that we need. The GL-5 has additives that could cause issues to his transmission over time. The few places where I've found GL-4 75W-85 gear oil, it has been $20 a quart, which means about $80 for the gallon I need. One place I was able to find a gallon for $65 shipped. It is so annoying, when SAE 90 weight gear oil is about $18 a gallon, and when I can get a 5 gallon pail of 75W-90 GL-4 synthetic for $90 shipped. Why is actual 75W-85 GL-4 specification gear oil so hard to find, and so expensive when we do track it down? (~3-5 times as expensive)

 

[heymrdj]

I think GL-4 is only made by like two brands at this point. Paying for limited run smaller batch kind of stuff. What you’re finding are the cheap options. Looking at the whole picture, paying 50$ more for oil beats rebuilding the whole transmission again when the GL-5 additives eat the soft metals in the GL-4 rated transmission.

 

[Jimzz]

This is the best bang for the buck GL-4

https://smile.amazon.com/gp/product/B000M8RYMC

1 gallon for $32. Yes that brand/viscosity will work fine.

 

[jlee]

Amsoil specs a GL4 75w90 - https://www.amsoil.com/p/manual-transmission-transaxle-gear-lube-75w-90-mtg/#pills-home_0

I can get that for you at wholesale if you want it. The stuff linked above from Amazon will be a lot cheaper.

 

[EXCellR8]

That amazon link is for 85W90... but yea should work fine.