Chevrolet 1980 Light Duty Truck Service Manual page 310

3E-8 WHEELS AND TIRES
Dual W heels
When installing wheels on vehicles with dual rear
wheels:
1. Install inner and outer wheel and clamp ring on
rear, or wheel and clamp ring on front (be sure pins on
clamp ring face outboard).
2. Install and snug nuts finger tight.
3. Torque nuts to specified torque in sequence shown
in Fig. 3E-12.
Lateral runout should not exceed 1/8" on front wheel
or 3/16" on rear wheel.
A ttachm ent of Dual W heels On P 3 0 0 Models
To assure secure attachment of the dual disc wheels,
it is important that all dirt or rust scale be removed from
the mating surface of the wheels, hub, and clamp ring as
well as the stud and nut. POWER DRIVE NUTS THEN
MANUALLY INSPECT TORQUE AT 130-180 FT. LBS.
MANUAL TORQUE ONLY: 150-200 FT. LB.
Side and Lock Rings
Side and lock rings of different rim types are not
interchangeable. Some may appear to be, but they do not
fit peoperly on the rim base. Serious accidents have resulted
from the use of mismatched rings. Rim base and rings must
be matched according to manufacturer, size and type. This
information is stamped on each part.
Inspection for Leaks
1. With wheel assembly removed from vehicle, inflate
the tire to recommended operating pressure.
2. Check for leaks at rim bead by placing wheel and
tire horizontal and allowing water to stand in groove
between rim and tire. Check for other leaks by lowering
assembly into water tank or running water over tire.
Installing Synthetic Tubes
When tube and flap are not properly
NOTICE:
lubricated and mounted, they will stretch thin in the
tire bead and rim region. This will cause premature
failure.
1. Before installing tube in tire, clean inside of casing
thoroughly.
2. Insert tube in tire and inflate until it is nearly
rounded out.
3. Inspect rim for rust scale and bent flanges-clean
rust scale and straighten flanges where necessary.
4. Using a brush or cloth swab, apply a solution of
neutral vegetable oil soap to the inside and outside of tire
beads and also the the rim side of the tube. Do not allow
soap solution to run down into tire.
5. When mounting tire and tube on a drop center rim,
follow the standard procedure. Be sure tire is centered on
rim so that beads are out of rim well before inflating. Do
not allow tire to hang loosely on wheel while inflating.
6. Center valve and pull it firmly against the rim. Hold
in this position and inflate until tire beads are firmly seated
on rim against flanges.
7. Completely deflate tire by removing valve core.
8. Reinflate tire to recommended pressure.
TUBELESS TIRES
Tubeless tires mounted on one piece full drop center
rims are standard on some trucks. These tires have a safety
inner liner which if punctured, tends to cling to the
penetrating object forming a partial seal until the object is
removed from the tire.
M ounting and Demounting
Use a tire changing machine to mount or demount
tires. Follow the equipment manufacturer's instructions. Do
not use hand tools or tire irons alone to change tire as they
may damage the tire beads or wheel rim.
Rim bead seats should be cleaned with a wire brush or
coarse steel wool to remove lubricants, old rubber, and light
rust. Before mounting or demounting a tire, the bead area
should be well lubricated with an approved tire lubricant.
After mounting, inflate to 40 psi so that beads are
completely seated.
CAUTIO N: Do not stand over tire when
inflating. Bead may break when beads
snaps over safety
serious personal injury.
Do not exceed 2 7 5
pressure when inflating. If 2 75 kPa (40
psi) pressure w ill not seat beads, deflate,
re-lubricate and reinflate. Overinflation
may cause the bead to break and cause
serious personal injury.
Install valve core and inflate to proper pressure. Check
the locating rings of the tire to be sure they show around
the rim flanges on both sides (Fig. 3E-14).
hump and cause
kPa (40 psi)
LIG H T T R U C K S ER V IC E M ANUAL