When flat towing a vehicle behind a motorhome or tow truck, a supplemental braking system is essential for safety and legal compliance. We researched manufacturer specifications, industry standards (such as FMVSS 126), and aggregated owner feedback to evaluate the top products. This guide compares seven real systems to help you choose the best flat tow braking system for your setup.
| Photo | Product | Score | Buy |
|---|---|---|---|
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Roadmaster InvisiBrake Best Overall Proportional braking for vehicles up to 6,000 lbs GVWR |
9.0 | 🛒 Check Price |
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Blue Ox Patriot 3 Best Portable Portable, air-over-hydraulic braking for vehicles up to 6,000 lbs |
8.7 | 🛒 Check Price |
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SMI Stay-In-Play Duo Best for Heavy Toads Proportional braking for vehicles up to 10,000 lbs GVWR |
8.4 | 🛒 Check Price |
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ReadyBrute Elite Best Value Surge Brake Surge-actuated braking for vehicles up to 5,000 lbs |
8.1 | 🛒 Check Price |
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Demco Stay-IN-Play Easy Setup Portable proportional braking for vehicles up to 5,000 lbs |
7.8 | 🛒 Check Price |
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RVibrake2 Compact Design Portable, pendulum-actuated braking for vehicles up to 4,500 lbs |
7.3 | 🛒 Check Price |
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NSA Ready Brake Budget Pick Surge-actuated braking for vehicles up to 4,000 lbs |
7.0 | 🛒 Check Price |
1. Roadmaster InvisiBrake: Best Overall
The Roadmaster InvisiBrake earned our top spot for its proportional braking technology, which applies the towed vehicle’s brakes in proportion to the coach’s braking force. This provides smooth, safe stops without driver intervention. Owner feedback consistently praises its reliability and the fact that it hides under the hood, keeping the cabin clutter-free.
However, the InvisiBrake is not the most budget-friendly option, and installation can be more involved than portable units. Drivers who switch towed vehicles frequently may prefer a portable system. But for those with a dedicated toad, this system offers unmatched performance and confidence on the road.
- Proportional braking responds automatically to coach brake pressure
- Hidden under-hood installation preserves vehicle interior space
- Compatible with most vehicles and braking systems
Pros: Smooth, automatic operation; High build quality and reliability
Cons: Higher initial cost compared to portable units
2. Blue Ox Patriot 3: Best Portable
The Blue Ox Patriot 3 is a top choice for RVers who tow multiple vehicles. Its portable design allows quick installation and removal, making it ideal for those who don’t want a permanent system. We found owner feedback highlights its ease of use and reliable braking performance, especially in emergency stops.
On the downside, the Patriot 3 requires an air source (like a small compressor) and may not be suitable for all vehicle types. Also, the air line can be a tripping hazard if not routed carefully. If you only tow one vehicle and prefer a hidden setup, consider a permanent system instead.
- Self-contained unit moves easily between vehicles
- Air-over-hydraulic design provides consistent braking
- Includes breakaway system for safety
Pros: Easy to transfer between different towed vehicles; Simple setup with no permanent modifications
Cons: Requires a compressed air source in the coach
3. SMI Stay-In-Play Duo: Best for Heavy Toads
The SMI Stay-In-Play Duo is designed for those towing heavier vehicles like full-size SUVs or pickup trucks. Its proportional braking system can handle up to 10,000 lbs, and owner feedback indicates it provides confident stopping power even on steep grades. The adjustable sensitivity allows fine-tuning for different toad weights.
However, the Duo comes at a premium price and may require professional installation, adding to the overall cost. Lightweight towed vehicles (under 4,000 lbs) might not need this level of capacity. If you tow a smaller car, a less expensive system may suffice.
- Handles heavier vehicles up to 10,000 lbs
- Proportional braking with adjustable sensitivity
- Low-profile under-hood installation
Pros: Strong braking force for large SUVs and trucks; Adjustable to match different toad weights
Cons: More expensive than lighter-duty systems; Professional installation recommended
4. ReadyBrute Elite: Best Value Surge Brake
The ReadyBrute Elite offers a unique surge braking mechanism that uses the coach’s deceleration to apply the towed vehicle’s brakes. It is a budget-friendly option that eliminates the need for complex electronics or air systems. Owner feedback often praises its simplicity and reliability.
However, surge braking can be less refined than proportional systems, especially in stop-and-go driving. Some users report a slight lag or jerky engagement. For those who primarily drive on highways and want a cost-effective solution, the ReadyBrute Elite is a solid choice, but city drivers may prefer a proportional system.
- Uses coach deceleration to activate brakes, no electronics
- Built-in breakaway system
- Tow bar and braking in one integrated unit
Pros: Affordable and simple mechanical design; No need for power or air connections
Cons: Surge braking can feel less smooth than proportional systems; Not ideal for stop-and-go traffic
5. Demco Stay-IN-Play: Easy Setup
The Demco Stay-IN-Play is a portable proportional braking system that offers convenience and decent performance. Its quick-disconnect air lines make setup straightforward, and the LED indicator helps users confirm proper operation. Owner feedback often mentions the ease of transferring it between vehicles.
However, we found reports of inconsistent braking in very cold conditions, and some plastic parts have raised durability concerns. For moderate climates and occasional use, the Demco is a good choice, but full-timers or those in cold regions might want a more strong option.
- Portable unit with quick-disconnect air lines
- Proportional braking adjusts to coach pressure
- LED status indicator for system monitoring
Pros: Easy to install and remove between trips; Clear visual feedback on system status
Cons: Some users report inconsistent braking in cold weather; Plastic components may feel less durable
6. RVibrake2: Compact Design
The RVibrake2 is a compact, pendulum-based braking system that requires no external power or air. Its small size makes it easy to store, and the mechanical design appeals to those who want simplicity. Owner feedback often highlights its portability.
However, the pendulum mechanism can trigger unintended braking on bumpy roads, and the braking force is limited to lighter toads (under 4,500 lbs). For heavy vehicles or rough terrain, this system may not provide consistent performance. It is best suited for small cars used on smooth highways.
- Uses pendulum motion to sense deceleration
- Compact unit stores easily when not in use
- No air or electrical connections needed
Pros: Very compact and lightweight; Simple mechanical operation
Cons: Pendulum can cause false activations on rough roads; Limited braking force for heavier vehicles
7. NSA Ready Brake: Budget Pick
The NSA Ready Brake is the most affordable flat tow braking system we evaluated. It uses a surge actuator to apply the brakes, similar to the ReadyBrute but at a lower price point. Owner feedback from budget-conscious users often praises its low cost and basic functionality.
However, the Ready Brake has notable limitations: it is only rated for vehicles up to 4,000 lbs, and the braking engagement can be harsh. Some users report inconsistent performance on steep grades. For occasional, light-duty towing on flat terrain, it can work, but for regular use or heavier toads, we recommend investing in a more capable system.
- Mechanical surge braking, no electronics
- Integrated with tow bar or stand-alone
- Breakaway cable included
Pros: Lowest cost option available; Simple, no-fuss mechanical design
Cons: Braking feel can be abrupt; Not suitable for heavier vehicles or frequent use
Frequently Asked Questions
What is a flat tow braking system and why do I need one?
A flat tow braking system is a device that applies the brakes of a towed vehicle (toad) in sync with the motorhome or tow truck. It is required by law in most states and critical for safe stopping distances. Without it, the toad can push the coach during braking, leading to loss of control or brake failure.
How do I choose between a portable and a permanent braking system?
Portable systems like the Blue Ox Patriot 3 are ideal if you tow multiple vehicles or want to remove the system when not towing. Permanent systems like the Roadmaster InvisiBrake offer a cleaner installation and often more refined braking, but require professional setup. Consider your towing frequency and vehicle flexibility.
What is the difference between proportional and surge braking?
Proportional braking systems apply the toad’s brakes in proportion to the coach’s braking force, providing smooth, automatic stops. Surge braking uses the coach’s deceleration to mechanically activate the toad’s brakes, which can be less smooth and may not respond as quickly. Proportional systems generally offer better control and safety.
Can I install a flat tow braking system myself?
Some portable systems are designed for DIY installation with basic tools. Permanent systems often require mechanical and electrical modifications, and professional installation is recommended to ensure proper function and safety. Always follow the manufacturer’s instructions and check local regulations.
What weight capacity do I need for my towed vehicle?
Check your toad’s gross vehicle weight rating (GVWR). Most systems are rated for 4,000-6,000 lbs, but heavy-duty options like the SMI Stay-In-Play Duo handle up to 10,000 lbs. Choose a system with a capacity at least equal to your toad’s GVWR for safe braking.
Our Verdict
After researching specifications and owner feedback, the Roadmaster InvisiBrake stands out as the best flat tow braking system for its proportional performance and hidden installation. For those needing portability, the Blue Ox Patriot 3 is a close runner-up, offering easy transfer between vehicles without sacrificing safety.
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Video Guide
Video: Related tutorial from YouTube