A lot of vehicles (SUVs, crossovers, wagons and minivans particularly) come loaded down with factory roof racks that are rarely if ever used by their owners. The aerodynamic penalty of roof racks at highway speeds can be significant: they increase both the vehicles frontal area and its drag coeffecient (Cd, or CoD). They also add a significant amount of weight to the top of the vehicle which reduces fuel effeciency and stability, which itself reduces fuel economy.
Removal is usually easy (aftermarket) to moderately difficult (OEM). Removed racks can be reinstalled when needed. A compromise for OEM racks with difficult to remove side rails/mounts is to remove just the crossbars. This removes a great deal of surface area from the front of the vehicle as well as another obstacle for air to pass over. Furthermore it allows the side rails to provide a small amount of flow attachment to the top of the vehicle.
Instructions for mod
Unscrew roof rack.
Check your workshop manual for details as removal will be application specific.
Please enter your user name and any relevant data in the table
|User Name||Car Make, Model, Year||Cost of Mod||Time to Perform Mod||MPG Before Mod||MPG After Mod||MPG improvement guess||Instruction Link|
|External user||$0||0.5 to 2 Hours||48.2 Empty roof racks|| No rack - 55.23
Bike on rack - 40.1
| No rack - 14.6%
Bike on roof rack - -16.8
|Mini-experiment: the wrath of roof racks|
Problems / Consequences of mod
Reduced cargo capacity
Flow Field Features and Aerodynamic Drag of Passenger Car <<< Page 29, Roof racks