These premium grade cast iron hats make it possible to use bolt-on rotors on vehicles equipped with internal shoe parking brake assemblies. Each hat is a precision machined, threaded hole design for use in conjunction with through-hole mount rotors. After machining, the hats are zinc-plated for corrosion resistance. Use the charts below to match the rotor mount circle, lug pattern, offset, and other dimensions necessary for each application.

View Technical Drawing

Rotor
Bolt Cirlce

Wheel
Lug Pattern

Hat
Offset

Stud Hole
Diameter

Center
Hole I.D.

Face
Thickness

Clearance
I.D.

Mount
Hole

Hat Part
Number

Rotor Bolt
Kit Number

12 x 8.75"

5 x 4.50/4.75/5.00"

1.95"

.52"

2.78"

.18"

6.85"

1/4-28

170-9493

230-8217

12 x 8.75"

5 x 4.50/4.75/5.00"

1.54"

.52"

2.78"

.18"

6.85"

1/4-28

170-9492

230-8217

12 x 8.75"

5 x 4.75"

1.53"

.52"

2.78"

.25"

7.10"

1/4-28

170-8169

230-8217

12 x 8.75"

5 x 4.50"

2.16"

.51"

2.69"

.20"

6.65"

1/4-28

170-9455

230-8217

12 x 8.75"

5 x 4.50"

1.32"

.51"

3.54"

.20"

6.11"

1/4-28

170-9599

230-8217

8 x 7.78"

5 x 4.50/4.75/5.00"

2.80"

.52"

3.06"

.18"

6.63"

1/4-28

170-6240

230-6409

8 x 7.78"

5 x 4.50/4.75/5.00"

2.39"

.52"

3.06"

.18"

6.63"

1/4-28

170-6239

230-6409

8 x 7.78"

5 x 4.50/4.75/5.00"

1.71"

.51"

2.29"

.26"

6.54"

1/4-28

170-6983

230-7011