Step 3: attach wheels to axle – Northstar Trailers MULTISTAR User Manual
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STEP 3: ATTACH WHEELS TO AXLE
Note: the hub assembly comes attached to the wheels with pre-lubricated bearings and
washers. Upon removing the dust-caps take special care to not drop the bearings or get them
dirty.
a. Carefully remove dust-cap from the wheel (7) by gently prying around the edges of
the cap with a small, flathead screwdriver, or by using a long bolt to gently drive
through the backside of the hub and into the cap.
b. Remove the outer bearing, flat-washer and tabbed-washer from the interior of the
hub, and then set aside.
c. Carefully slide the wheel onto the end of the axle.
d. Slide the bearings into the hub; press into place carefully as to not remove any
grease.
e. Place the flat-washer on the bearing, followed by the tabbed-washer. Ensure that
the washers are snug with and pressed flat against the axle.
f. Fully tighten the castle-nut against the bearings to the point that the nut applies
enough pressure against the bearings to lock them into place. Then, loosen the
castle nut approximately ¼”, or to the point where the wheel can spin; the nut
should be loose enough that the wheel freely spins, yet tight enough that the wheel
does not have horizontal play or wiggle. The final castle-nut tension will be
approximately 35 ft-lbs. (Proper tension is critical to the longevity of the bearings).
g. Align a slot of the castle-nut with the tabbed washer so the washer tabs appear in
the slots of the nut, then use a screwdriver to bend one of the washer tabs into a
notch of the nut. This is very important to ensure the integrity of the hub assembly.
h. Attach a grease gun to the hub’s Zirk fitting—located on each end of the axle—, and
apply pressure until you can see grease extruding from the bearing casing.
i. Replace the dust-cap by tapping it into place with a rubber mallet. RTV sealant or
silicon may be applied to the circumference of the dust-cap before installation to
ensure that the cap will not fall off while in tow. Let the sealant completely dry
before towing.
Note: the dust-cap has an exterior Zirk fitting access, and does not need to be removed to
grease the bearing. Grease the wheel bearings a minimum of 1x per year for normal use, and
up to 3x per year for frequent use in order to ensure the longevity of the bearings. Adjust and
re-grease the bearings after the first 100 miles.