Overall Length of the Demco DM8104311 Surge Brake Actuator
Updated 07/25/2026 | Published 07/20/2026
Question:
How much overall frame length does the DM8104311 use including the solenoid extension? I need to know if I will still have room for the trailer jack.
asked by: William
Expert Reply:
Hi again William! The Demco part # DM8104311 measures approximately 31-5/8 inches in overall length, including the electric lockout solenoid that extends from the rear of the actuator. The main actuator body itself measures about 16-1/4 inches long, so you'll want to plan for the full 31-5/8 inches when making sure there's enough room on your trailer tongue for both the actuator and your trailer jack.
If you can measure from the front of your trailer tongue back to where your jack is mounted and compare that to the 31-5/8 inch overall length, you'll have a good idea of whether everything will fit comfortably before making the swap.
One quick question that will help me make sure you're looking at the right replacement. Does your trailer have disc brakes or drum brakes? I only ask because you were asking about drum brakes on a previous question. what style of trailer jack do you have, and is it mounted directly behind the coupler or a little farther back on the tongue?
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Product Page this Question was Asked From
Demco Surge Brake Actuator w Drop and Electric Lockout - Disc - Zinc - 2-5/16" Ball - 12.5K
- Brake Actuator
- Surge Brake Actuator
- Boat Trailer
- Construction Trailer
- Farm Trailer
- Travel Trailer
- Utility Trailer
- Bolt-On
- 12500 lbs GTW
- 2-5/16 Inch Ball Coupler
- 3 Inch Channel Tongue
- Disc Brakes
- Electric Lockout
- Demco
more information >
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