Wilwood W4A Big Brake Rear Parking Brake Kit - Manual (Page 3)

Installation of this kit should ONLY be performed by persons experienced in the
installation and proper operation of disc brake systems. Before assembling the
Wilwood rear axle disc brake kit, double check the following items to ensure a
trouble-free installation.
•Make sure this is the correct kit to fit the axle housing flange, not necessarily the
rear end make. Many times after market manufacturers put a different make of axle
housing flange on the stock rear end housing (see Figure 5). Example; Big Ford
rear ends with Olds-Pontiac flanges, therefore, an Olds-Pontiac rear disc brake kit
would be the correct kit to order. Also, shock clearance may be a problem. They
may have to be modified and/or relocated to clear the Wilwood kit after final
assembly.
•Inspect the package contents against the parts list to ensure that all components
and hardware are included.
•Verify The Following Measurements Before Assembly.
• Bearing outside diameter.
• Axle housing flange mounting pattern to pattern in bracket.
• Stud pattern on axle flange to stud pattern in hat.
• Axle center register diameter is 2.80”, Figure 3. This kit uses Wilwood’s
removable center register adapters. Rotors can either be centered on the axle
register, i.e. register-centric or centered on the wheel studs, i.e. stud-centric.
Due to variations in wheel stud final diameters, register-centric centering can
be a more accurate method of centering the rotor to the axle. Wilwood offers
various diameter adapters for purchase in addition to the ones supplied in this
kit, see Table 1.
Figure 2. Wheel Clearance Diagram
CENTER
LINE OF
WHEEL
.50 (12,7)
RADIUS 0.0 (0,0)
3.72 (94,5) .20 (5,1)
4.59
(116,6)
8.05
(204,5)
CALIPER
WILWOOD ROTOR
WHEEL MOUNT SURFACE
NOTE: A MINIMUM OF .080” CLEARANCE MUST BE MAINTAINED
BETWEEN THE WHEEL AND CALIPER IN ALL AREAS
1.10 (27,9) ROTOR THICKNESS
2.80 (71,1)
CENTER REGISTRATION
Parts List
General Information
1
2
3
3A
4
5
6
7
8
9
10
11
12
12A
13
14
15
16
17
1
2
2
2
24
24
2
6
1
12
12
2
2
2
4
4
4
16
2
249-9774/75
170-9493
160-8402/03
160-8400/01-BK
240-11240
230-6738
249-10955/56
230-6318
150-9488K
240-10191
240-9609
300-9504
120-11659/60
120-11659/60-RD
230-9182
240-11101
230-9080
240-1848
300-11337 Bracket Kit (pair, one each, left and right)
Hat, 5 x 4.50/4.75/5.00, 1.95 offset, 12 x 8.75 Bolt Circle
Rotor, GT 1.10” Thk x 14.00” Dia, 12 x 8.75” Bolt Circle, Right & Left
Rotor, Black, SRP Drilled and Slotted
Washer, .265 I.D. x .500 O.D. x .063 Thick
Bolt, 1/4-28 x .75 Long, 12 Point
Bracket Caliper Mounting (pair, one each, right and left)
Bolt, 5/16-24 x 1.75 Long, SHCS
Pad, BP-10 Compound, Axle Set
Washer, .328 I.D. x .562 O.D. x .063 Thick
Shim, .015 Thick
Spacer, Caliper Bracket
Caliper, W4AR (pair, one each, right and left)
Caliper, W4AR, Red
Nut, 7/16-20 Self-Locking, 12 Point
Washer, .453 I.D. x .750 O.D. x.063 Thick
Stud, 7/16-14 x 7/16-20 x 3.375 Long (pre installed in bracket)
Washer, .441 I.D. x 1.003 O.D. x .030 Thick Shim
Adapter, Rotor Registration
ITEM NO. PART NO. DESCRIPTION QTY
NOTES: P/N 230-8217 Rotor Bolt Kit, includes part numbers 230-6738 and 240-11240
P/N 250-10957 Caliper Mounting Bracket Kit, includes P/N’s 230-9182, 230-9080, 240-1848, 240-11101 and 249-10955/56
P/N 300-9739 Spacer Kit, includes part numbers 230-6318, 240-10191, 240-9609 and 300-9504
Item 3A is an optional item and included with the (D) drilled rotor kits. Add “-D” to end of part number when ordering.
Item 12A is an optional item and included with the (R) red caliper kits. Add “-R” to end of part number when ordering.
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