The telltale whistling and wind noise generated by roof racks and cargo carriers can quickly become an annoyance. But what actually causes the bothersome sounds, and is there any way to diminish the rack-induced ruckus? This comprehensive guide examines the science behind roof rack noise, evaluates options for reducing wind resistance, and provides tips for the quietest roof rack setup. Follow these insights to stop the sounds of roaring wind and enjoy the utility of cargo hauling up top in peace.
Why Do Roof Racks Make Noise
| Rack Type | Noise at 50 mph | Noise at 75 mph |
|---|---|---|
| Crossbar rack | Moderate | Very loud |
| Cargo basket | Very loud | Extremely loud |
| Cargo box | Minimal | Moderate |
| Watersport carrier | Moderate | Loud |
This table summarizes the typical noise levels produced by common roof rack types at 50 mph and 75 mph speeds. It shows that aerodynamic cargo boxes are quietest while open crossbar racks and especially cargo baskets, create the most wind noise.
Roof Rack Noise Reduction Product Reviews
Ready to upgrade your roof cargo hauling to achieve a quieter drive? Here are my top product recommendations:
Best Roof Cargo Box
Thule Motion XT Rooftop Cargo Box
- Aerodynamic design with tapering
- Dual-side opening for easy access
- Security and weatherproofing features
- Noise reduction technology
Quietest Roof Rack Crossbars
- Aerodynamic profile with aero strips
- Multiple width options
- Durable and lightweight
- Super slick to minimize wind noise
Best Wind Fairing
Thule Aero Extended Roof Fairing
- 60″ length for maximum turbulence reduction
- Durable ABS plastic construction
- Quick DIY installation
- Designed specifically for noise reduction
Top Wind Deflectors
- Reduce trailing turbulence off bars
- Clamp or adhesive options available
- Can tilt to optimize wind diversion
Investing in smart, noise-reducing products prevents headaches from loud whistling and helps you better enjoy the expanded cargo capabilities of roof rack hauling.
The Aerodynamics of Roof Rack Noise
Roof racks inherently create turbulence as air passes over your vehicle. But several factors impact the intensity of noise generated:
Turbulence Factors
- Rack design (fairings, rounded bars)
- Number of crossbars
- Speed of driving
- Cargo carrier box or basket
- Luggage positioning on racks
This airflow disruption and resulting sounds increase proportional to your vehicle’s speed. The noise generating turbulence occurs in two main ways:
Buffeting Zone Behind Bars
Crossbars and support towers leave a wake of turbulent airflow behind them as your car moves forward. This unstable air in the ‘buffeting zone’ creates noise:
Tip Vortexes at Bar Ends
The squared ends of roof bars also spin air into vortexes as it spills off the sides. These turbulent tip vortices intensify noise:
So the fundamental rack structures prompt unavoidable noise. But smart choices in design, cargo carriers, and driving habits can help reduce wind roar.
How Speed Impacts Roof Rack Noise
The faster you drive, the more intense turbulence and resulting noise become:
Aerodynamic roof cargo carriers like rocket boxes may add only 5 decibels (dB) of sound at 50 mph. But open bar roof racks or cargo baskets can create around 20 dB more noise at the same speed.
At 75 mph, the difference becomes exponential – enclosed cargo adding ~10 dB versus open setups approaching 30+ dB louder.
“The key takeaway is that aerodynamic cargo boxes will be reasonably quiet up to highway speeds. But open racks or baskets get extremely noisy as you drive faster, especially above 65 mph.” – Steve Miller, Christensen Automotive
So if you’ll routinely drive on highways, focus on enclosed cargo carriers or use fairings to smooth airflow as speed increases.
Roof Rack Styles and Noise Levels
Not all roof racks and cargo carriers are equal when it comes to wind noise. Here’s how the main setups compare:
Crossbar Roof Racks
- Noisiest since fully exposed to wind
- Round bars slightly quieter than square
- Bars spaced close together increase noise
Noise level: Moderate at low speeds, Very Loud above 50 mph
Roof Cargo Baskets
- Mesh design catches wind like a sail
- Some models have curved side blades to mitigate wind
Noise level: Very Loud, Worsens above 55 mph
Roof Cargo Boxes
- Aerodynamic enclosed design
- Tapered front helps air pass over smoothly
- Lockable and protective of gear
Noise Level: Quiet at Lower Speeds, Moderate Noise above 65 mph
Watersport Carriers
- Lower profile than cargo baskets
- Foam pads prevent hull abrasion
- Require bow and stern tie downs
Noise Level: Moderate, Less Than Cargo Baskets
So for minimal wind noise, opt for sleek cargo boxes or lower profile carriers like watersport racks. Limit open bar use to around-town driving.
Add-On Accessories for Noise Reduction
While cargo carriers themselves impact noise levels, you can further fine tune rack setups for quieter airflow using:
Wind Fairings
- Mounted on leading edge of crossbars
- Tapered shape smoothly diverts wind
Deflectors
- also called wind visors or shields
- Attach on bar trailing edge
- Streamline turbulence
Air Strips
- Adhesive rubber strips
- Attach along top of bars
- Reshape bluff body to rounded
While not eliminating all wind noise, these add-ons help streamline airflow and reduce turbulence to make racks reasonably quiet up to highway speeds.
Tip to Minimize Roof Rack Wind Noise
Along with proper gear selection, small adjustments in how you outfit and drive your roof rack make a big difference in limiting loud wind sounds:
- Remove empty racks when not in use
- Carry gear inside vehicle if possible
- Lower profile carriers over tall cargo baskets
- Enclosed cargo boxes over open racks
- Limit crossbar numbers to what’s needed
- Round bars create less noise than square
- Wider bar spacing if load allows
- Bar spread matters more than height
- Angle front bar back slightly
- Face cargo carriers rearward
- Wrap unusual gear to reduce drag
- Secure loose items that could flap
- Fairings and shields over naked bars
- Slower speeds and relaxed acceleration
Taking the time to purposefully arrange your rack system for slipperier airflow makes a world of difference in reducing bothersome whistling and wind noise.
“Roof racks may always generate some level of wind noise. But with smart selections and proper streamlining, you can minimize turbulence and prevent that constant ‘whoosh’ giving you a headache on long drives.” – Steve Miller, Christensen Automotive
Embrace the Versatility Despite Some Wind Din
At the end of the day, roof racks enable more gear transport flexibility which makes slight wind noise an acceptable trade-off. Follow the tips in this guide to select rack components and add-ons that smooth airflow as much as possible. But also embrace the joys of racks and carriers when used judiciously for cargo that truly benefits from rooftop transport. Just be sure to secure all loads properly, adjust driving for wind resistance, and pump up the music to mask any remaining wind rush.
