Changing front axle to gear oil question

[loggin]

Hello everyone; I have been considering changing my front axle from UDT to gear oil. Either 80w90 or 75w90 synthetic. The manual says that I can use 80w90 as a replacement.
My question is do I have to flush out the UDT and then do a final fill with gear oil or can I just drain and fill with the gear oil and have the small amount of UDT left in the bottom
of the hubs just mix with the new oil?

Any comment on procedure and/or grade would be greatly appreciated

 

[CausticUrbanCoast]

The usual reason not to switch is that you have enough leftover in the pail from changing your hydraulic fluid to fill the front as well. One less oil hanging around on a shelf.

 

[5030]

Drain out the UDT and refill with gear oil. How I did it way back when (3000+ hours ago)... Of course I've changed it a few rimes since then.

I prefer gear oil for the shock load mitigation aspect more than anything else.

 

[CausticUrbanCoast]

Drain out the UDT and refill with gear oil. How I did it way back when (3000+ hours ago)... Of course I've changed it a few rimes since then.

I prefer gear oil for the shock load mitigation aspect more than anything else.

Final drives switch to gear oil? I am out of date.

 

[5030]

Some Kubota's (mine included) use a separated axle and final drive configuration where the final drives are lubricated with lubricant separately from the axle and have their own fill, level and drain plugs and those also get gear oil, not just the axle casting. Not sure which models have a separated cavity and which don't. I see some also have Alemite (zerk) fittings to lubricate the king pin and upper seal and some don't. Mine does. Kind of wish my tie rod ends had grease fittings as well as I just replaced one this spring and OEM tie rod's aren't cheap.

 

[denmis]

I had a small leak with the UDT, so I changed to 80/90 Gear Oil about 100-150 hrs ago, and the leak went away. All I did was drain and fill, and have had no problems since.

 

[RalphVa]

Doubt there is that much difference to justify flushing. I'd just drain and refill with the gear oil. Doubt there are very few additions in either stuff.

 

[loggin]

Thank you all very much for your responses!! I did eventually hear back from the dealership and they also confirmed that it would be alright to simply do a drain and fill.
I have to say I do prefer the added protection from GL-5 gear oil in the axle and will likely do the switch.

Enjoy the weekend and stay safe!!

 

[CausticUrbanCoast]

Just check your axle often if you switch to an SAE, when it emulsifies, drain and dry the water out. It will happen more often if you have wide temperature swings.

 

[loggin]

Just check your axle often if you switch to an SAE, when it emulsifies, drain and dry the water out. It will happen more often if you have wide temperature swings.

Sorry for my ignorance but does this mean gear oil is more likely to be contaminated with water than UDT over time?