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
Last edited: