LS 3025 front axel fluid

[LS Mike]

My 2017 xg3025hd front axel requires 80w90 gl4 gear oil but i keep finding gl 5. What is the differance and can i use gl 5?

 

[Dman1981]

gl5 is better protection for extreme pressure I use synthetic in all my customers front axles my weed abatement guy is 1k hours a year
No problems

 

[JCoastie]

Discover the Difference - GL4 vs GL5 Gear Oil | VP Racing

What's the difference between GL4 vs GL5 gear oil? The main difference is the amount of extreme pressure (EP) additives. GL5 has more EP than GL4.

vpracingfuels.com

"They make GL4 gear oils with enough EP additives to protect spur and helical gears in manual transmissions. A GL4 will maintain the necessary balance of viscosity, detergency, and corrosion protection.

This type of oil is perfect for vehicle gear applications with high levels of yellow metals. An API GL5 gear oil has higher levels of active sulfur phosphorous, which will corrode yellow metals."

"A GL5 gear oil has about twice as much EP additive as a GL4, ensuring the greatest protection, performance, and efficiency for your hypoid gear system."

Thinking is that tractors rarely use yellow metals, so GL5 should be both just fine, and better than GL4 in that application. Like @Dman1981 I also use a synthetic GL5 in my front axle.

 

[Texasmark]

I have a 65 HP 4wd tractor that I abused....very rough 1st smoothing after plowing, bucket full of gravel to help to smooth out the ride.......I broke both front axle bearings. OEM front end oil was the same as in the hydro/tranny/differential. After fixing the problem, I installed 85w-140 and haven't looked back....that was 15 or so years ago.

Same company machine, 2016 year model rather than 2009 of the other tractor, 25 HP, 4wd, in the Operator's manual specs and molded in the plug that is used to check the front axle fluid it stated 90w.

Ok, having read on here where some folks have broken their front axles doing this and that I put 85w-140 in it too....living here in N. Tx., had no problem with the thicker oil, have worked the tail off this little 25 hp and it too has had no problems.

Moral of this story as I see it, if the manufacturer some years later, changes the front axle oil on a 25 hp tractor vs a much larger 65 hp tractor from thin to thick there is obviously something to it and it needs to be heeded.....I did and haven't been sorry.

Yellow metal is in older transmissions, usually used for synchronizers of the steel gears and their shafts. I don't see a place for yellow metal in 4wd front ends so I see no reason to worry about GL-5 which is the rating of the heavy oil I currently use in my 4wd tractors and have had zero problems.