Mowing deck service. Deck is a rCK60D-26BX. Manual says to use 90w gear oil, which no local parts store carries. Is it ok to use the Kubota 80w90 gear oil as a replacement?
Thank you.
Thank you.
Mower Deck Gear Oil
- Thread starter WhatnxtBX
- Start date
Gear oil is lightweight oil. Don't let the labels fool you. Check again at your local parts store for 80-90 wt oil. Maybe none comes as 90 only...80-90 will work just fine. Gear oil usually comes in a plastic bottle (maybe a quart) with a tapered top with a removeable stopper cap. (The bottle is about the circumference of a tube of caulking.) Clip off the top to the place that will give the opening size you want and stick it into the opening you want to fill. If you don't use it all, the stopper cap keeps it from spilling. It also comes in larger containers but to fill a mower gear, the tapered top would be ideal. I hope this helps...you're on the right track.
Tractor Gal
Tractor Gal
For a mower deck, I could not imagine it being even remotely necessary, considering the change interval & service conditions.
SHORT ANSWER
GL-5
LONG ANSWER
NOBODY has been able to run the GL-4 certification tests for over 30 years. API allowed OEMs to continue to use the GL-4 designation for existing formulations (long since gone) and new GL-5 formulations where the EP treat rate was reduced by half. That ended in 201? when API OFFICIALLY removed the GL-4 designation from use. Anybody claiming GL-4 today is making it up.
Now to your yellow metal concern. GL-4 was NEVER about yellow metal protection. The GL-4 specification had essentially the same limits on yellow metal corrosion (ASTM D130 -2B) as GL-5. GL-5 simply provided better EP wear protection.
Now if thats not enough for you over those decades just about every formulator has replaced older active sulfur EP additives with newer buffered/inactive sulfur. The result is the majority of modern GL-5 formulations exhibit almost no yellow metal corrosion - 1A or 1B staining on the ASTM D130 tests.
Now back to my popcorn.
Dan
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Your choice.
I use synthetic in all my equipment from cars to tractors. That's just my preference. Never tried to push it on anyone. My tractor, my choice.
I chuckled a little.
Seems every 2nd gearbox we have leaks enough that buying the expensive stuff just doesn't seem worth it. We buy it by the five gallon bucket and simply fill everyone up before we use it. They never seem to break, but they always seem to leak.
Keeping them full seems to trump putting expensive oil in.
Seems every 2nd gearbox we have leaks enough that buying the expensive stuff just doesn't seem worth it. We buy it by the five gallon bucket and simply fill everyone up before we use it. They never seem to break, but they always seem to leak.
Keeping them full seems to trump putting expensive oil in.
I run synthetic in all my vehicles, and also in my tractor. They are applications that can really take advantage of the benefits brought on with a modern synthetic fluid.
The gearbox on a mower deck isn’t one of those places, so I don’t.
However, if it makes you feel warm and fuzzy, run the hell outta it. Your tractor, your mower, your money.
It doesn't cost that much more to go first class.
Cheaper then lunch at Mcdonalds
Cheaper then lunch at Mcdonalds
Except I at least get the benefit of weapons-grade diarrhea from the McDonalds.
Synthetic gear oil in a mower deck that gets changed annually is legitimately just pouring money into the waste oil bin.
Purple dye is cheap and can be added to any oil.
I buy 80/90 gear oil in 5 gal buckets for some construction equipt I own.… So I also use it in the front axle of the Kubota tractor, and the gearboxes of Augers and Shredders, etc…..
The point of my post is that I buy a cheap garden sprayer and cut the nozzle off the wand…. and use the calibrations on the tank to assist in dispensing it into whatever machine needs it. (I have several such garden-sprayers and dedicate them for various fluids.)
This is Especially-Useful when dispensing oil into an area difficult to access or pour-into with ordinary jugs or bottles. In this pic I am completing an oil-change with engine oil. The filler-neck of my M4700 is impossible to access without spilling… I use the “locking trigger” feature of the wand….but must stay-close or I’ll forget and over-fill.
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