PREVOST X3-45 Multiplex, Maintenance Manual

Page: 733 / 1422

5
29
Dualed wheels, stud
located, ball seat
mounting (contin-
ued)
NOtICE: Do not exceed
maximum wheel load.
Cus tomer must compare
OEM vehicle load rating to
maximum wheel load rating.
Refer to tire manufacturer’s
recommendation for proper
tire pressure. Be fore mounting
the tire perform a wheel
fitment check to insure
proper clearance from any ob-
structions.
NOtICE: Check for and
replace bent, broken, cracked
or damaged studs. When
replacing broken studs, always
replace the studs on each
side of the broken stud. If two
or more studs are broken,
replace all the studs for that
wheel position. Check with
the stud manufacturer for
regular maintenance and stud
replacement practices.
All wheel fastener hardware
should be grade 8 or metric
conversion 10.9. Follow the
hardware manufacturer’s
recommendations when
replacing studs.
Most vehicles have standard length studs (1.31" [1-5/16"] to 1.44" [1-7/16"] stud standout). Some
vehicles use studs longer than standard (up to 1.88" [1-7/8"] standout).
When changing types of brake drums be sure to check for excessive stud standout (greater than 1.88"
[1-7/8"]). All states and provinces have their own standards for fastener engagement. Most of these
consist of at least 1 to 2 threads past full thread engagement. Excessive stud standout may cause the
inner cap nut to bottom out on the longer stud preventing proper seating of the wheel.
Each outer dual wheel is attached by 10 single cap nuts which thread on the inner cap nuts. Use
Alcoa outer cap nuts, Part Nos. 5996R, 5996L or equivalents. Match mounted dual wheels should be
put on the vehicles with the valve stems 180° apart.
Disc Mate wheel spacers are recommended for use with Alcoa Dura-Bright
®
surface treated wheels
to protect the wheel contact surfaces from marring. Disc Mate wheel spacers are placed between the
contact surfaces of the Dura-Bright
®
wheel and the brake drum and between the dual aluminum
On occasion Alcoa aluminum truck wheels are operated dualed with a steel inner wheel. When this
application occurs it is recommended to use a Disc Mate, because of corrosion issues. In the event a
steel inner wheel is used, extreme care must be exercised to properly seat it to the hub or drum prior
to mounting the outer aluminum wheel. Selection of an inner cap nut capable of fixing the steel inner
wheel and providing adequate external thread length to secure the outer aluminum dualed wheel is
critical to a safe assembly. Alcoa recommends the use of inner cap nuts 7896R and L (Grade 8), or equiva-
lent, for this purpose.
Correct mounting for dual aluminum, stud located / ball seat mount wheels.
WARNING Incorrect inner cap nuts used with dualed aluminum wheels can bottom out on
the unthreaded portion of the stud before the wheels are properly seated.
Improperly seated wheels can run loose, cause stud breakage and disengage from the
vehicle which can cause serious injury or death. Loose running wheels can lead to stud
breakage.
Use only cap nut 5978R or L, 5988R or L, or their equivalent when mounting dual alumi-
num wheels.
WARNING
Alcoa Aluminum Wheels
Drum
3/4” Stud
Hub
Outer Cap Nut
P/N 5996R or L
(See 5-2, page 26)
1.31" to 1.44"
stud standout
Inner Cap Nut
P/N 5978R or L
or P/N 5988R or L
(See 5-2, page 26)
Disc Mate (when used)