Table of Contents
Advertisement
Tire Matching
Both tires on the same spindle must be the same size in
order to properly distribute the load and braking forces
between them. The tire must be mounted on a rim and
properly inflated before measuring. If there is an
allowable difference in size the smaller tire should be
mounted to the inside position of the duals.
Tape Measuring Method
Measure around each tire on the tread surface. A
maximum difference of 3/4" is allowed between the two
mating tires of a dual
(See Figure
Figure 4-15: Measuring Tape Method
Tire Changing Procedure
1. Set tractor brakes
2. Set trailer brakes.
3. Place jack under trailer frame (not under axle) and lift
until tire clears ground.
4. If trailer is loaded, place jack under each side of
trailer frame and lift trailer evenly.
Straight Edge or String Method
(This method cannot be used if tire and wheel
assemblies are not mounted on the axle.) Jack trailer up
until the wheels are off of the ground. Hold a straight
edge against the tires of both ends of an axle. A gap at
one tire indicates a smaller tire. A maximum of 1/8" gap is
allowed
(See Figure
4-16.)
TABLE OF CONTENTS
4-15.)
MAINTENANCE AND LUBRICATION
STRAIGHT EDGE
Figure 4-16: Straight Edge Method
Mounting Tire and Wheel
1. Make sure that all mounting surfaces are clean and
free of rust, dirt or paint. A wire brush may be used to
clean these surfaces
2. Position the inner disc wheel over the studs, being
careful not to damage the stud threads. Make sure
that the disc wheel is flat against the mounting
surface and that there is clearance between the disc
wheel taper and brake drum.
3. Position the outer disc wheel being careful not to
damage the threads. Be sure the valve stems for
both the inner and outer tire are accessible.
4. Install the flange nut and tighten to 50 foot-pounds
using the sequence in
to full torque of 500 to 550 foot-pounds.
5. Torque will drop after the first 50 to 100 miles of
operation. Check the nuts for proper torque after this
interval and retighten them.
WARNING
Use a torque wrench to assure proper torque.
Insufficient torque can cause stud breakage and
damage wheel pilots. Overtorque can overstress
the studs and strip the threads.
(See Figure
4-17.)
See Figure
4-18. Then tighten
4-23
Advertisement
Table of Contents
