What is a Tie Rod?

rack and pinion steering linkage

A tie rod is a system that connects the steering mechanism and the wheels. There are several types of steering linkages but all of them involve tie rod ends in one form or another. Some use a drag link that connects to a bar with tie rod ends on each side that in turn connect to the wheels, others have an inner and outer tie rod end connected to the outer wheels and a rack and pinion system in the center. In all cases the tie rod ends are essential for controlling a vehicle and when they become worn down or damaged then turning or even maintaining a direction can be difficult.

cross steering linkage

What Does a Tie Rod Do?

The main function of the tie rod is connecting the steering to the wheels, but it also plays a role in keeping the wheels in alignment. In addition to this, the tie rod ends also provide some flexibility in the steering so that the bumps and jolts that the tires experience on the road are cushioned on their way to the steering wheel.

The downside to this is that the tie rod ends are constantly absorbing those bumps and can begin to wear down and loosen over time. On top of this every time the steering wheel is moved those joints are being engaged, adding to the wear and tear that these parts go through.


Symptoms of a Bad Tie Rod

bad tie rod end symptoms

A bad tie rod is actually one or more bad tie rod ends. Since these are essential for steering, problems with the steering is where you will likely notice the first symptoms. If the steering wheel feels loose or is excessively vibrating or shaking you may have worn or loose tie rod ends. Other symptoms can include vehicle vibration, uneven and premature tire wear, or clunking or clicking sounds coming from the front end when turning. There are other suspension and steering components that can cause similar symptoms so its a good idea to check your tie rod ends if you suspect they are causing your problems.

Check out this article for more information on the symptoms of bad tie rod ends.

Other components that can display similar symptoms are the ball joints, control arm bushings, and steering rack bushings.


How to Check for a Bad Tie Rod

To check the tie rod you need to try and move the tie rod ends by hand and look for looseness or play. Besides play in the joint you need to check for moisture inside the seal, damage to the dust boot, or corrosion on the stud. If you've noticed some of the symptoms of a bad tie rod but haven't ruled out other possible causes then checking the tie rod ends is the easiest way to narrow it down.

  • Checking for looseness in the actual tie rod ends by hand is a pretty simple process and can be done without jacking up the vehicle and you should be able to tell if the tie rod end is bad without much trouble. Just remember: Outer tie rod end shouldn't move vertical, inner tie rod end shouldn't move horizontal. And don't use a pry bar or excessive force since even a good tie rod end will move with enough pressure.
  • Alternatively if you can observe the underside of the vehicle while someone else moves the steering wheel back and forth rapidly you can observe the same movement in the tie rod ends if they're bad (outer moving up or down, inner moving front to back).
  • Checking the dust boots for damage can also be a good indicator that a tie rod is headed for trouble soon. This is a little more intense since getting a good look at the whole seal requires jacking up the vehicle and taking the wheels off. Better to check those when you already need to take the wheels off for other reasons.

How Long do Tie Rods last?

worn tie rod ends

Tie rods could last as long as you own the vehicle, but this is usually the exception rather than the rule. The tie rod ends are essentially a wear and tear part in that the smooth, lubricated metal surfaces inside are designed to handle a lot of friction, but eventually natural wear will cause looseness in the tie rod ends and your steering.

This is without even considering the possibility of circumstances that could cause the joint to wear prematurely. If moisture enters the joint you could end up with corrosion that will break down the articulating surfaces. Debris could make it's way into the joint and even something as insignificant as some sand could be problematic as it is ground between the stud and bearing of the joint. Also, rougher than average driving conditions can put extra stress on the tie rod and accelerate the wear process. All of these factors can affect the lifespan of a tie rod.


How Much Does it Cost to Replace a Tie Rod?

The cost of replacing tie rod ends ranges between $20-$100 for the parts and another $50-$120 for labor depending on the difficulty. The cost varies widely based on the make and model of vehicle and the difficulty and length of the repair.

As with all things there are different levels of cost and quality when it comes to replacement tie rod ends. Off brand tie rod ends can be much cheaper but the quality is often questionable and there may not be a warranty. Premium aftermarket parts from reputable brands can be more expensive but the quality reflects the price and you generally get a warranty against defect in the part.

Since we're talking about cost it's important to note that not replacing worn or damaged tie rod ends can accelerate the wear of other steering and suspension components making more replacements necessary and costing more in the long run.


How to Grease Tie Rod Ends

how to grease moog tie rod ends

Lubricating a tie rod end helps it function correctly and last longer. The process of greasing a tie rod end with a grease zerk fitting is fairly straight forward and similar to the process of greasing other chassis and suspension parts, but there are some tips and tricks that will make the going smoother.

Some of the biggest concerns are checking the dust boot for damage and making sure not to bust the seal between the dust boot and the housing of the tie rod end. If your tie rod ends do not have grease fittings then they are not designed to accept more grease and if they are emitting a squeaking or whine as though they are running dry then they likely need to be replaced. If they aren't showing any of the other symptoms and you need them to last a little bit longer then you can get a little grease through the boot using a needle attachment, but this is only a stop gap measure and you should be looking for replacement rod ends.

For a full and detailed run down check out how to grease tie rod ends here.


Best Grease for Tie Rod Ends

tie rod end grease rating

There are some factors to consider when choosing the best grease for your tie rod ends but any grease rated "GC-LB" by the National Lubricating Grease Institute (NLGI) will work for tie rod ends.

Tie rods endure a lot of punishment and the smooth metal surfaces need to be able to easily articulate with the constant movement of the steering wheel and vibration from the road. The lubricating grease in-between the surface of the ball stud and the bearing must be up to the task, or the smoothness of your steering may begin to grind. A bit of good news is that you can use the same grease for your other articulating joints and greasable chassis parts so that maintenance can all be taken care of in one go.

We have two lubricant suggestions from Lucas Oil:

  • X-Tra Heavy Duty - for daily drivers or recreational vehicles in dryer climates
  • Marine Grease - for vehicles operating in coastal or wetter climates

Check here to learn more about the best grease for tie rod ends.


Moog Tie Rod Ends

moog tie rod end

If you are in need of some replacements, Moog tie rod ends are an excellent aftermarket part that is designed to last longer than other replacement parts and even the original equipment. Moog is a leader in aftermarket replacement chassis, steering, and suspension parts with wide coverage and a history of quality. Moog calls their parts "Problem Solvers" and with the many benefits that set them apart from other replacement options its easy to see why. Some of those benefits include:

  • Moog tie rod ends use a Greasable Design, where applicable, allowing them to be properly maintained for increased longevity.
  • The powered metal Gusher Bearing in Moog's tie rod ends provides reduced friction and a grease permeable bearing for smoother operation.
  • A pressed in cover plate and bellville washer prevents looseness in the tie rod end over time for a longer effective lifespan.
  • Wrench flats on the rod end make installation or removal at home an easy process.

If you find yourself needing a inner or outer tie rod replacement be sure to check out Moog for a longer lasting part. For custom jobs or hard to find replacements you can check the measurements you need and find a suitable fit with the Universal Tie Rod End Chart.

* Disclosure: We sell Moog Parts, but we do so becuase we have found them to be a reliable and quality option for replacement parts.