80w gl-4 hypoid gear oil?

[Lightman]

JOhn, thanks for the reply. That's what redline said as well. Here's a quote from the email.

"GL-4 Denotes lubricants intended for axles with spiral bevel gears
operating under moderate to severe conditions of speed and load or
axles with hypoid gears operating under moderate speeds and loads.

GL-5 Denotes lubricants intended for gears, particularly hypoid
gears, in axles operating under various combinations of high speed
shock loads and low speed, high torque conditions.

From the service designation descriptions you can see that both GL-4
and GL-5 lubes are suitable for use in hypoid applications. By
convention though a hypoid gear lube refers to a GL-5 lubricant, an
EP gear lube suitable for use in severe duty high offset hypoid ring
and pinion gear sets. A hypoid gear requires an extreme pressure gear
lube due to the high stress imposed in operation."

 

[Lightman]

I'm a little confused though, as it seems to suggest GL-5 is the right rating for hypoid gears, yet on mobil's web site, it says their synthetic 75w90 gear oil is good for use with anything BUT hypoid gears...

 

[Senor Quack]

quote:

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Originally posted by Lightman:
I'm a little confused though, as it seems to suggest GL-5 is the right rating for hypoid gears, yet on mobil's web site, it says their synthetic 75w90 gear oil is good for use with anything BUT hypoid gears...

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I went right to their website and found no mention of this. In fact, it goes on and on from the get-go about how good it is for hypoid gears. Anyways, just go with the Redline 75w-80 initially suggested and you can't go wrong. It's ester-based, so it has excellent shear-strength.

I don't know much about ATV's, so I had no idea if the front gearbox has syncronizers or not. If not, just use the same oil both front and back and ignore the MTL, it's not ideal for a differential.

 

[Lightman]

I was mistaken earlier - it was actually the GL-4 mobil 424 fluid that specifically mentioned not for hypoid use. Kinda surprised me because that's the fluid specified for my prairie's rear diff and wet braking system. I was hoping to be able to use the same stuff but no dice.

Dave at Redline explained to me that the MTL could work, although the 75w80 stuff has 5% friction modifier and may work better due to being super slippery. We'll see.

Thanks to those that helped.

 

[MolaKule]

I don't know of the conversation between you and Dave at Redline but MTL DOES NOT have a sufficient EP package required for hypoid gears, plain and simple.

Senor Quacck and others are correct. Go with RP Maxgear or Redline 75W80-90.

One needs to consider BOTH viscosity and EP protection when dealing with gears.

 

[Lightman]

I ordered redline 75w80.