Brands Vehicles
Lowest Prices
Free Returns
Online Since 2009
JOIN GEARS TO SAVE 5%
Shop All Brands Shop All Vehicles

  2. Auto Parts
  3. Brake System
  4. Drums and Rotors
  5. Brake Drum
  6. ACDelco 18B503

ACDelco 18B503 Brake Drum

ACDelco 18B503 Brake Drum Image 1
ACDelco 18B503 Brake Drum Image 2
ACDelco 18B503 Brake Drum Image 3
ACDelco 18B503 Brake Drum

ACDelco
Brand:ACDelco
Part Number: 18B503
UPC: 00707773005682
Weight: 19.9 lbs
Condition:New



Availability:
0 in Stock
 OUT OF STOCK

Product Information

Description:

DRUM,RR BRK (B)

ACDelco Professional Brake Drums are constructed with G3000 SAE qualified material for structural integrity and maximum service life. They are tested to ISO/TS 16949 quality system standards and validated for balance to provide better braking performance. Chamfer angle, vane configuration, and plate thickness all follow the OE design, making them a premium aftermarket replacement for your GM and non-GM vehicle. Also, no machining is required. ACDelco Professional Brake Drums are ready to be installed right out of the box. ⚠ WARNING: Cancer and Reproductive Harm - https://www.P65Warnings.ca.gov

Features and Benefits:

  • Follows original manufacturers' designs for dispersing heat, helping to prolong pad and rotor life while reducing noise and vibration
  • Independently tested with Noise/Vibration/Harshness (NVH) and durability/wear testing; resulting in high quality and reliable products
  • Inspected for balance; resulting in smooth brake operation and noise reduction

Specifications:

ABS Tone Ring Included:
No
Bolt Circle Diameter (in):
6.5 in
Bolt Circle Diameter (mm):
165.1 mm
Bolt Hole Quantity:
8
Brake Surface Finish:
Turned
Center Bore Diameter (in):
4.6in
Center Bore Diameter (mm):
116.8mm
Depth:
2.43 in.
Depth:
61.7 mm
Discard Thickness (in):
12.06 in
Discard Thickness (mm):
306.3 mm
Grade Type:
Regular
Height (in):
4 in
Length (in):
12.06 in
Material:
Cast Iron
Maximum Brake Diameter (Discard):
306.32 mm
Mount Hole Diameter (in):
0.536in
Mount Hole Diameter (mm):
13.614mm
Nominal Drum Diameter:
0.475 in.
Nominal Drum Diameter:
12.05 mm
Outer Cooling Fins:
No
Outside Diameter:
0.536 in.
Outside Diameter:
13.6 mm
Programming Required:
No
Stud/Lug Hole Diameter:
0.528 in.
Stud/Lug Hole Diameter:
13.4 mm
Stud/Lug Hole Quantity:
8
Weight:
19.9 lb
Width (in):
14.6 in

Features and Benefits:

  • – Calipers and wheel cylinders should be checked every brake inspection and serviced or replaced as required.
  • – Check brake fluid level at every oil change. Replace fluid according to owner's manual recommendations.
  • – Check the thickness of your brake pads.
  • – Inspect the brake lines for rust, punctures, or visible leaks (You may be able to do this, but consult a qualified technician if necessary).
  • – Inspection of brake lining and pads for wear or contamination by brake fluid or grease.
  • – Inspection of the brake hoses for brittleness or cracking.
  • – Inspection of wheel bearings and grease seals.
  • – Parking brake adjustments (as needed).
  • The following inspections and maintenance procedures can help prevent potential brake problems:
  • The following should be conducted by a qualified technician:

Specifications:

Country of Origin:
CN

Select a vehicle to narrow ACDelco 18B503 Brake Drum fitment info!

Last Updated: 03/03/2024

Years Vehicle Per Vehicle Position Fit NotesFitment Notes

1959

 

1959

 
Chevrolet 3E

3.8L L6 Gas OHV,
4.6L V8 Gas OHV
2
 
Front
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet 3E



3.8L L6 Gas OHV,
4.6L V8 Gas OHV

Front Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1959

 

1959

 
Chevrolet 3E

3.8L L6 Gas OHV,
4.6L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet 3E



3.8L L6 Gas OHV,
4.6L V8 Gas OHV

Rear Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1967

 

1966

 

1967

 

1966

 
Chevrolet P20 Series

2.6L L3 Diesel OHV,
4.1L L6 Gas OHV
2
 
Rear
 
Professional
 

Chevrolet P20 Series



2.6L L3 Diesel OHV,
4.1L L6 Gas OHV

Rear Professional

2 Per Vehicle

1967

 

1966

 

1965

 

1964

 

1963

 

1967

 

1966

 

1965

 

1964

 

1963

 
Chevrolet P20 Series

4.8L L6 Gas OHV
2
 
Rear
 
Professional
 

Chevrolet P20 Series



4.8L L6 Gas OHV

Rear Professional

2 Per Vehicle

1965

 

1964

 

1963

 

1962

 

1961

 

1960

 

1965

 

1964

 

1963

 

1962

 

1961

 

1960

 
Chevrolet P20 Series

3.8L L6 Gas OHV
2
 
Rear
 
Professional
 

Chevrolet P20 Series



3.8L L6 Gas OHV

Rear Professional

2 Per Vehicle

1962

 

1961

 

1962

 

1961

 
Chevrolet P20 Series

4.3L L6 Gas OHV,
4.6L V8 Gas OHV
2
 
Rear
 
Professional
 

Chevrolet P20 Series



4.3L L6 Gas OHV,
4.6L V8 Gas OHV

Rear Professional

2 Per Vehicle

1961

 

1960

 

1961

 

1960

 
Chevrolet P20 Series

5.7L V8 Gas OHV
2
 
Rear
 
Professional
 

Chevrolet P20 Series



5.7L V8 Gas OHV

Rear Professional

2 Per Vehicle

1958

 

1957

 

1958

 

1957

 
Chevrolet Truck

4.6L V8 Gas OHV
2
 
Front
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



4.6L V8 Gas OHV

Front Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1958

 

1957

 

1958

 

1957

 
Chevrolet Truck

4.6L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



4.6L V8 Gas OHV

Rear Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1958

 

1957

 

1956

 

1955

 

1954

 

1953

 

1958

 

1957

 

1956

 

1955

 

1954

 

1953

 
Chevrolet Truck

3.8L L6 Gas OHV
2
 
Front
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



3.8L L6 Gas OHV

Front Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1958

 

1957

 

1956

 

1955

 

1954

 

1953

 

1958

 

1957

 

1956

 

1955

 

1954

 

1953

 
Chevrolet Truck

3.8L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



3.8L L6 Gas OHV

Rear Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1957

 

1956

 

1955

 

1957

 

1956

 

1955

 
Chevrolet Truck

4.3L V8 Gas OHV
2
 
Front
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



4.3L V8 Gas OHV

Front Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1957

 

1956

 

1955

 

1957

 

1956

 

1955

 
Chevrolet Truck

4.3L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



4.3L V8 Gas OHV

Rear Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1955

 

1955

 
Chevrolet Truck

4.3L L6 Gas OHV
2
 
Front
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



4.3L L6 Gas OHV

Front Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1955

 

1955

 
Chevrolet Truck

4.3L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



4.3L L6 Gas OHV

Rear Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1953

 

1953

 
Chevrolet Truck

3.5L L6 Gas OHV
2
 
Front
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



3.5L L6 Gas OHV

Front Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1953

 

1953

 
Chevrolet Truck

3.5L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
with 4.850in Wide Drums
 

Chevrolet Truck



3.5L L6 Gas OHV

Rear Professional
with 12 IN Brakes
with 4.850in Wide Drums

2 Per Vehicle

1959

 

1958

 

1959

 

1958

 
GMC 150

5.5L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



5.5L V8 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1959

 

1958

 

1957

 

1959

 

1958

 

1957

 
GMC 150

6.1L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



6.1L V8 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1959

 

1958

 

1957

 

1956

 

1959

 

1958

 

1957

 

1956

 
GMC 150

4.4L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



4.4L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1959

 

1958

 

1957

 

1956

 

1955

 

1959

 

1958

 

1957

 

1956

 

1955

 
GMC 150

5.3L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



5.3L V8 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1957

 

1957

 
GMC 150

5.7L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



5.7L V8 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1956

 

1955

 

1956

 

1955

 
GMC 150

5.2L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



5.2L V8 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1955

 

1955

 
GMC 150

4.7L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



4.7L V8 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1955

 

1954

 

1953

 

1955

 

1954

 

1953

 
GMC 150

4.1L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



4.1L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1953

 

1953

 
GMC 150

3.7L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150



3.7L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1955

 

1955

 
GMC 150-22

4.7L V8 Gas OHV,
5.2L V8 Gas OHV,
5.3L V8 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150-22



4.7L V8 Gas OHV,
5.2L V8 Gas OHV,
5.3L V8 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1955

 

1954

 

1953

 

1955

 

1954

 

1953

 
GMC 150-22

4.1L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150-22



4.1L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1953

 

1953

 
GMC 150-22

3.7L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150-22



3.7L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1954

 

1953

 

1954

 

1953

 
GMC 150-24

4.1L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150-24



4.1L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1953

 

1953

 
GMC 150-24

3.7L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 150-24



3.7L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1963

 

1963

 
GMC 1500 Series

3.8L L6 Gas OHV,
4.8L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 1500 Series



3.8L L6 Gas OHV,
4.8L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1963

 

1962

 

1961

 

1963

 

1962

 

1961

 
GMC 1500 Series

4.6L V8 Gas OHV,
5.0L V6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 1500 Series



4.6L V8 Gas OHV,
5.0L V6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1962

 

1961

 

1962

 

1961

 
GMC 1500 Series

4.3L L6 Gas OHV,
4.4L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC 1500 Series



4.3L L6 Gas OHV,
4.4L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle

1967

 

1967

 
GMC P25/P2500 Van

2.6L L3 Diesel,
4.1L L6 Gas OHV,
4.6L V8 Gas,
4.8L L6 Gas
2
 
Rear
 
Professional
 

GMC P25/P2500 Van



2.6L L3 Diesel,
4.1L L6 Gas OHV,
4.6L V8 Gas,
4.8L L6 Gas

Rear Professional

2 Per Vehicle

1953

 

1953

 
GMC Truck

3.7L L6 Gas OHV,
4.1L L6 Gas OHV
2
 
Rear
 
Professional
with 12 IN Brakes
 

GMC Truck



3.7L L6 Gas OHV,
4.1L L6 Gas OHV

Rear Professional
with 12 IN Brakes

2 Per Vehicle