Kubota BX1880, BX2380, BX2680 HST Oil Filter Replacement

BX1880 / BX2380 / BX2680 Owner Service Guide

The HST oil filter cleans the transmission fluid that feeds the hydrostatic transmission and the hydraulic system. It is replaced at the first 50 hours and then every 200 hours. Kubota specifies a genuine Kubota filter to protect the hydraulic system. Some fluid is lost when the filter comes off, so the transmission level has to be checked and topped up afterward.

Interval	First at 50 hours, then every 200 hours
Time	20 minutes
Tools	Oil filter wrench, drain pan, rag
Parts	HST oil filter, Kubota Super UDT-2 fluid for top-up

Warning. Stop the engine before changing the HST oil filter. Transmission fluid can be hot enough to burn; let it cool first. Park on firm, level ground with the implement lowered.

Replacing the filter

Park on firm, level ground, lower the implement, set the parking brake, stop the engine and remove the key.
Place a drain pan under the HST oil filter on the transmission case.
Remove the filter with a filter wrench.
Wipe the mounting surface clean and make sure the old seal came off with the filter.
Put a film of clean transmission fluid on the rubber seal of the new filter.
Thread the new filter on by hand quickly until the seal contacts the mounting surface.
Tighten it by hand an additional 1/2 turn.
Start the engine, run it briefly, and check that no fluid leaks from the filter seal. Stop the engine.
Check the transmission fluid level and top it up as described below.

HST oil filter on the transmission case — HST oil filter.

Checking and topping up the transmission fluid

The transmission oil fill and dipstick are at the rear of the tractor, above the three-point hitch.

With the tractor on level ground, the implement lowered and the engine off, pull the dipstick.
Wipe it clean, push it fully back in, and pull it out again.
The fluid level must be between the two notches.
If it is low, add Kubota Super UDT-2 through the oil fill opening a little at a time and recheck.

Do not run the tractor with the transmission fluid below the lower notch. Check the level the same way before each day of use.

Transmission oil fill and dipstick at the rear of the tractor — Transmission oil fill and dipstick. Level must be between the notches (A).

Total transmission case capacity is 11.3 L (3.0 U.S. gal.). That amount is only needed when the fluid is changed, which is a separate 400-hour service.