Oil & Fuel Kubota L3430 HST 4WD Front Gearcase Oil Leak

[bdhsfz6]

Shortly after doing the 700 hour tractor maintenance, I noticed a minor but annoying oil leak at the wheel pivot point on the left front gear case. The tractor had recently been used for extended periods during hot weather. The exhaust is also on that side which just increases the temperature in that area.

The recommended lubricant for the front gear case is UDT or Super UDT hydraulic fluid which doesn't appear to be much thicker than water at high temps. The manual also permits the use of 80 W 90 gear oil which has a much higher viscosity. In an attempt to stave off the expense of replacing the oil seal, I'm thinking of switching to the heavier lubricant to slow or stop the leak at least temporarily.

From other posts, I know these compact tractors are prone to front gear case leaks and there has been much discussion on oil viscosity. My question is, has anyone managed to slow or stop such a leak by switching to higher viscosity oil?

 

[number two]

The answer is yes!
Many owners have switched to gear lube in the front axle and have reduced the leakage.
I'm not sure anyone has completely stopped the leaking by switching,but maybe someone will post that has.
The best preventative measure is to always use plenty of rear counterweight to reduce the front axle loading and the associated wear and tear.
Good Luck!

 

[bdhsfz6]

Just a follow up on my earlier post:

After switching from Kubota's Super UTD oil to 80 W 90 gear oil in the front gearcase, the leak initially slowed and eventually stopped almost completely. There is a "wet look" to the narrow space between the upper and lower gearcase housings but no measurable loss of oil. Prior to the switch, I was adding about a quart of UDT per week.

 

[Jay4200]

Just a follow up on my earlier post:

After switching from Kubota's Super UTD oil to 80 W 90 gear oil in the front gearcase, the leak initially slowed and eventually stopped almost completely. There is a "wet look" to the narrow space between the upper and lower gearcase housings but no measurable loss of oil. Prior to the switch, I was adding about a quart of UDT per week.

I'm assuming you're referring to the bezel seal. Stupid design, IMHO (even though 99% of 4x4s use it) where dirt sits on the top of the lower piece and grinds the seal to pieces. It is possible that you had a grain of sand stuck in the seal that came out - happens with dirt bike fork seals anyway. I'm up to 90W140 in my front axle to keep the bezel seal leaks to a slow roar.

 

[bdhsfz6]

Yes, I was referring to the bezel seal. I agree about the poor design. Kubota, and other makes have been using variations of it for a long time. The L3430 is my 4th Kubota and the only one to develop this leak. I won't get a chance to see how well the heavier weight oil holds during really hot weather since I just traded the machine for a MX5800. It uses the same seal design though so I'll know what to do if it leaks.