GMC 1982 Light Duty Truck Service Manual page 401

A. Tube Type Tires
1. Only use rims approved for radial tire usage by rim
manufacturer. Thoroughly clean rim parts, removing
all rust and other foreign material. M ake sure rim
parts match and are not sprung or broken'.
2. T horoughly lubricate tire beads, portion of tube
between beads, and flaps with an approved rubber
lubricant. Radial tubes are identifiable by the letter
" R " in the size designation. Example 100R20. Also,
to further identify the radial tube, a red band on the
valve stem has been required since March, 1975.
Radial flaps are also identified by the ietter " R " .
Example - 20R8.
NOTICE:
Do not use silicone base lubricants - this could
cause the tire to slip on the wheel.
3. Double inflate. Inflate to operating pressure, deflate
completely and reinflate to operating pressure. This
allows tube, flap and tire to fit together properly.
4. Check bead seating. Visually check slot and side ring
gap (on two piece rim) to make sure bead is seated.
The flange and one of the three lower sidewall rim
line rings while the tire is laying flat (measurements
should be taken each 90° around the circumference
of the rim flange). If spacing is uneven around bead
from side to side, repeat Step 1 through 3, and
recheck.
B. Tubeless Tires.
1. Only use rims approved for radial tire usage by rim
manufacturer. Thoroughly clean rim, removing all
rust and other foreign material.
2. Thoroughly lubricate tire beads and rim bead seats
with an approved rubber lubricant.
NOTICE:
Do not use silicone base lubricants - this could
cause the tire to slip on the wheel.
3. Inflation. Inflate tire to operating pressure. Due to
the construction of radial truck tires, particularly in
the lower sidewall and bead area, it may be difficult
to get the tire to take air. An inflation aid may be
necessary to help seat the bead of tubeless radial
tires. Two types of inflation aids are commercially
available, (1) metal rings which use compressed air
to seat beads, and (2) rubber rings which seal
between the tire bead and rim bead seat allowing the
bead to move out and seat. Lubrication is mandatory
with both items.
4. Check bead seating. This check is made by
measuring the space between the rim flange and one
of the three lower sidewall rim line rings while the
tire is laying flat (measurements should be taken
each 90° around the circumference of the rim flange.
If spacing is uneven around the bead from side to
side, repeat Steps 1 through 3, and recheck.
It's important that this procedure be followed to insure
proper bead seating in order to prevent bead deformation.
Radial tires, as well as the bias tires, must be mounted
and inflated in accordance with safety precautions noted in
R M A Radial and Bias Truck Tire Service Manuals.
TIRE REPAIR
There are many different materials and techniques on
the market to repair tires. As not all of these work on all
types of tires, tire manufacturers have published detailed
instructions on how and when to repair tires. These
instructions can be obtained from the tire manufacturer.
ALUMINUM WHEEL M AINTENANCE
Aluminum wheels can be cleaned, coated and painted
using the following procedure. Care should be taken during
entire procedure to avoid scratching or damaging the shiny
aluminum surfaces.
Materials Required
1. Amercian Sure Seal paint remover, product S T R IP
O F F - stock SSQ or equivalent.
2. 360 grit sand paper.
3. Nylon auto glass type scraper.
4. Amercian Sure Seal Silicone Remover - stock DSR or
3M # 8 9 8 5 W ax Remover.
5. Paint thinners.
6. American Sure Seal Aluminum Cleaner - stock DWC
or equivalent.
7. DuPont 228S conversion coating or equivalent.
8. Enamel color coat paint.
9. American Sure Seal Coricone 1700 Wheel Protector.
10. General purpose pads. 3M # 7 4 4 8 or equivalent.
11. American Sure Seal Glaze Cleaner - stock DG C or 3M
# 5979 clean and glaze.
12. American Sure Seal Wheel Polish - stock DAP or
equivalent.
PROCEDURE
1. Remove the wheel and tire assembly from the car.
After marking the wheel-tire relationship, remove tire
from wheel. If wheel and tire are not separated, mask
off the tire
WHEELS A N D TIRES
prior to painting
3E-9
and