Bull bars are aftermarket vehicle accessories made of rigid metal tubing that mount to the front of your vehicle's frame. They are designed to protect your bumper from damage in the event of a collision with an animal (hence the name "bull bar") or off-road obstructions, such as branches.
Bull bars mount on metal brackets that use the same holes in the frame as the factory tow hooks. Even on vehicles that do not have tow hooks installed, you shouldn't have to drill any holes in the frame. Simple hand tools and an assistant are all that's needed.
Remove the four bolts (two on each side) holding the factory tow hooks to the frame under the front bumper, using a socket wrench, if the vehicle is so equipped. Remove the tow hooks.
Position the bracket-mounting plates on top of the frame rail so that the bolts protrude down through the holes from which you removed the tow-hook bolts. On vehicles with no tow hooks, look for two holes on each side in the frame, directly behind the recessed areas at the bottom corners of the front bumper.
Place an L-shaped bracket over the protruding bolts from one of the two bracket-mounting plates and hold it in position. Slide a flat washer, a locking washer and a nut onto each bolt and tighten by hand. Do not over-tighten; doing so will prevent necessary adjustments when installing the bull bar. Repeat with the bracket on the other side.
Lift the bull bar into position with the help of an assistant and slide the ends over the brackets until the holes in the bull bar and the brackets line up. Instruct your assistant to hold the bull bar steady in this position.
Insert two bolts through the bull bar and one of the brackets, with the threaded ends of the bolts pointing toward the centre of the vehicle. Slide a flat washer, a locking washer and a nut onto each bolt and tighten by hand. Repeat on the other side of the bull bar.
Tighten the nuts holding the bracket to the frame with a socket wrench. Adjust the bull bar into the desired position in front of the bumper and have your assistant hold it there. Tighten the nuts holding the ends of the bull bar to the mounting brackets, using a crescent wrench to hold the bolt steady.
In vehicles with no factory tow hooks, it may be necessary to cut holes through the plastic bumper where the bull bar will attach to the mounting brackets. A reciprocating saw works well for this. A few vehicles may require you to remove the front bumper in order to easily install the bracket mounting plates. Most do not.