A vehicle tie rod is a component of the steering system. Some large SUVs, pickup trucks and older vehicles have the steering system that has a recirculating ball mechanism. Modern vehicles come with rack-and-pinion steering. Tie rods in both systems use the same function: they connect the steering rack or linkage to the steering knuckles. Let us examine how a tie rod functions in the rack-and-pinion steering system: the steering rack is linked to the car body, frame or subframe. Steering knuckles convey front wheels, see the diagram. When a driver turns the steering wheel, the steering rack slides and the tie rods turn the steering knuckles in the desired path
A tie rod is comprised of two components: inner and outer tie rod ends. Both tie rod ends have a ball joints. An inner tie rod end is greased and protected by the steering rack boot. The outer tie rod end is also filled with grease, but is protected by a small rubber or plastic boot. The most common issue with either tie rod ends is when they wear out and become loose. Usually this occurs when a rubber boot cracks or breaks and the moisture penetrates inside the tie rod end producing corrosion. Outer tie rod ends fail more often. Issues with tie rod ends are more common in heavier vehicles and SUVs because of greater load.
A loose or wobbling tie rod is a major safety issue as it can separate. If a tie rod end separates, the car will lose steering control. If you have observed a disabled car on the side of the road with the front wheels pointing in different directions, it’s likely one of the tie rod ends that has separated.
Signs of a loose tie rod end include a clunking, rattling or knocking noise in the front end and looseness felt in the steering. The issue is that often, a loose tie rod end may not give out any symptoms. Many mechanics will inform you that when the car comes for an oil replacement and a tie rod end (or some other components of the front end) is about to fall off, the owner might get very surprised to discover this. Because of this, the steering system, as well as brakes, suspension and other underneath parts must be checked at least once a year. The only way to properly check tie rods and other steering and suspension part is when the car is raised on a lift.
Can a bad tie rod produce shaking? Yes, an excessively worn tie rod ends produces a looseness in the steering This might result in shaking in the front end that comes and goes at some speeds. This issue is particularly common in older SUVs and pickup trucks with a recirculating-ball steering system. A weak steering damper makes this issue worse.
Tie rods are not very expensive to change. The outer tie rod replacement costs $20-$95 part plus $50-$110 labor. Changing the inner tie rod end costs a little more: $25-$102 part plus $60-$150 labor. In many vehicles, a special tool is needed to replace inner tie rod ends.
Does the car require the wheel alignment after changing a tie rod end? Yes, tie rods control steering angles. In fact, the tread or clamp connecting inner and outer tie rods is used to adjust steering angles. This implies that after the replacement of any of the tie rod ends, the car will require the wheel alignment to bring the steering and suspension angles back to within specifications. The wheel alignment could costs extra.
Should a tie rod end be changed on both sides at the same time? No, If a tie rod is in good shape, there is no need for replacement. Often, however, tie rods on both sides wear out at the same rate. If one tie rod goes bad and the other is starting to go, it makes sense to change both, so you won’t have to do the wheel alignment twice. Another reason to change a working tie rod end is when the protective boot gets damaged. Once that boot is damaged, the tie rod will not last long.
Should both, inner and outer tie rod ends be changed together? Again, there is no need to change the component if it’s good.
Does a tire rod require any maintenance? In some vehicles and trucks, tie rod ends come with grease fitting that must be greased periodically. In many modern vehicles, tie rod ends don’t require any maintenance as they are filled with grease and sealed at the factory. You can go through your owner’s manual or ask your mechanic to confirm if tie rods have grease fittings during a regular service.