Kubota BX1880, BX2380, BX2680 Toe-In Adjustment

BX1880 / BX2380 / BX2680 Owner Service Guide

Toe-in is the difference between the distance across the front of the front tires and the distance across the rear of the front tires. Kubota calls for checking it every 200 hours. Toe-in that is out of spec wears the front tires quickly and makes the tractor wander or pull. Bent tie-rods from hitting a stump or curb are the most common cause.

Interval	Every 200 hours
Time	20 minutes
Tools	Tape measure, two wrenches for the tie-rod lock nuts, torque wrench, tire gauge
Specification	Front distance 0 to 5 mm (0 to 0.2 in.) less than rear distance

Warning. Park on firm, flat, level ground. Lower any implement to the ground, set the parking brake, stop the engine and remove the key before measuring or adjusting.

Checking the toe-in

Set both front tires to the correct inflation pressure. A low tire changes the reading.
Drive the tractor straight ahead a few feet and stop with the front wheels pointed straight ahead.
Measure the distance between the tire beads across the rear of the front tires, at hub height. This is the rear distance.
Measure the distance between the tire beads across the front of the front tires, at hub height. This is the front distance. Measure at the same point on the bead on both sides.
The front distance should be 0 to 5 mm (0 to 0.2 in.) less than the rear distance. If it is within spec, no adjustment is needed.

Front wheels viewed from above, showing the front and rear measurement points — Front distance should be 0 to 5 mm (0 to 0.2 in.) less than the rear distance.

If the front distance is greater than the rear distance (toe-out), or the tractor has hit something, look at the tie-rods before adjusting. A bent tie-rod should be replaced, not adjusted around.

Adjusting the toe-in

There is a tie-rod on each side, running from the steering cylinder to the knuckle arm. Each has a lock nut at the outer tie-rod end.

Loosen the lock nut on each tie-rod.
Turn the tie-rods to change their length. Lengthening the tie-rods reduces toe-in; shortening them increases it. Turn both sides by the same amount so the steering stays centered.
Recheck the front and rear distances. Repeat until the front distance is 0 to 5 mm (0 to 0.2 in.) less than the rear distance.
Hold the tie-rod and tighten each lock nut to 55 to 61 ft-lbs.
Drive the tractor a short distance and check that the steering wheel is centered when traveling straight.

Front axle viewed from the front, showing the tie-rods and lock nuts — Tie-rods and lock nuts.

Tie-rod ends

While you are under the front axle, grab each tie-rod and check for play at the inner ball joint and the outer tie-rod end. Any looseness shows up as steering wheel play and makes the toe-in setting drift. Replace worn ends and recheck the toe-in afterward.

Parts

Part	Part number	Notes
Tie-rod	K1253-16604	2 per tractor
Tie-rod end, outer	K1252-01652	2 per tractor
Tie-rod lock nut	K1252-01640	2 per tractor
Inner ball joint	K1252-01630	2 per tractor