How to Measure Brake Drums
Published 12/08/2021
Question:
I have 40 year old drum brakes now That are electric. Is there a measurement I can take on the drum to know if these brakes will fit the existing drums? Thanks
asked by: Mark D
Expert Reply:
Yes, there is a measurement you can take to determine what size brakes you need and if they will fit your existing drums. You will want to measure the diameter of your drums. I have included a diagram detailing the dimensions you will need to find.
If you have 10 x 2-1/4 Inch drums then the etrailer Hydraulic Trailer Brake Kit - Uni-Servo - Free Backing - 10" - Left/Right Hand - 3,500 lbs item # AKFBBRK-35 you were looking at would fit your trailer.

Product Page this Question was Asked From
Hydraulic Trailer Brake Kit - Uni-Servo - Free Backing - 10" - Left/Right Hand - 3,500 lbs
- Trailer Brakes
- Hydraulic Drum Brakes
- Standard Grade
- Free Backing
- Manual Adjust
- Single Servo
- 10 x 2-1/4 Inch Drum
- 3500 lbs Axle
- 14 Inch Wheel
- 14-1/2 Inch Wheel
- 15 Inch Wheel
- etrailer
more information >
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