External Wear
Early hour wear pattern in Sealed Track
bushings are similar to those for Sealed
and Lubricated Track due to little or no
internal wear. Shown here are typical wear
patterns for late hour normal conditions
where internal wear has begun to have a
measurable pitch extension effect on the
external pattern.
Reverse Drive Side Wear is Critical
(30° to 65° from vertical)
CAUSES: Rotation and sliding against
sprocket under abnormal load (characteris-
tic of track loaders).
ACCELERATORS: Horsepower, weight
and speed; impact, abrasiveness, tight
track and high reverse working loads.
EFFECT: Cracks will occur on reverse
drive sides which becomes FDS after
bushing turned and will reduce bushings
total turned life.
REMEDIES: Reduce or eliminate control-
lable accelerator variables. Do not delay
turn past service point (100 percent) if turn
is required. Also, do not drive machine
long distance in reverse.
Forward Drive Side Wear is Critical
(30° to 60° from vertical)
CAUSES: Sliding motion of bushing against
sprocket under abnormal forward loads
(characteristic of push loading, drawbar,
ripping and dozing application).
ACCELERATORS: Same as “RDS Critical”
described above plus uneven terrain and worn
rear rollers.
EFFECT: Bushing wall worn through at
same position as internal wear is occurring
and may result in need for turn before
service point to avoid cracking if internal
wear is critical. It will not have same
effect on after-turn life of bushing as does
critical RDS wear.
REMEDIES: Eliminate or reduce control-
lable accelerator variables such as tight
track and worn rear rollers. Turn early if
internal wear is critical to prevent bushing
cracking.
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General Information
SEALED TRACK PINS & BUSHINGS