Car Feels Unstable At High Speeds – Why It Happened?

Your car feels unstable at high speeds. The scenario doesn’t sound positive, and you have reasons to worry about it.

The underlying causes are various, requiring proper actions to troubleshoot the problem.

I will include all the information about the issue to help you in this situation. Let’s get started!

Car Feels Unstable At High Speeds – Why Is That?

car feels unstable at high speeds

When your car feels loose at high speeds, you should consider different causes, such as the tire and wheel balance, worn tires, faulty shocks and struts, broken brakes, or even the engine failure.

You can fix some issues yourself, but if you’re not confident, I suggest you seek help from professionals for the sake of your safety and vehicle performance.

Tire Issues

If your car feels wobbly on the highway, stop and check your tire because it may be the cause of your issue. Common problems include improper tire pressure or uneven tire wear.

You can increase or decrease the amount of air to balance your vehicle. In most cases, the PSI should be equal between the front and back tires.

However, they might be different in some cases. You’d better refer to the manual to see the exact pressure needed.

Uninflated tires cause tread wear, while inflated ones make them become warped and wear even faster. That’s why your car swerves when driving straight.

Wheel Alignment

Unaligned wheels are another reason for the bad performance of the vehicle. Your car pulls left and right at high speeds because the wheel alignment angles are incorrectly set.

When one side of the tire wears more quickly, you also may need a car alignment. The shaking and vibration also indicate you may have a loose steering wheel.

Seeking help from auto mechanics is highly recommended.

Shocks and Struts

These components enhance stable driving on the road. When you make a turn, one side of your vehicle should be able to bear more weight.

Yet, if your car feels like it slides when turning, your shocks and struts are likely broken. A lubricant leak from the shock may be the indication of the problem.

I also often take further inspection by pressing hard on each corner and seeing how long it takes to bounce back.

If one corner does not return to its position as fast as the other three corners, you can assume the shock is damaged.


The complicated system of suspension components is subjected to wear and tear.

Deteriorated control arm bushings, tie rod ends, and ball joints are reasons why your car feels floaty at high speed. Malfunctioning ball joints also cause front or rear suspension creaking noise.

Motor Mounts 

Motor mounts are the details mounting the engine to the chassis. Since the motor is heavy, a faulty mount can lead to looseness and instability.

As the engine shifts position, your car feels like it’s swaying left and right.


You should pay attention to the brake when your car feels like it’s sliding, and it’s easy to confirm the brake disc’s status.

Run your vehicle at high speed, then press the brake. If you detect any vibration, it means there’s a sign of physical imperfection or exhaustion of the disc, requiring a replacement.

You can have the job done in authorized repair shops or roadside ones. But remember that stock brake discs are not easy to find in traditional workshops.

Moreover, the brake pads can be the reason why your car swerves at high speeds. You should also check them, especially when your brake pedal is squeaking.

The braking system plays an important role in your driving safety, so anytime you can’t optimize the brake, fix it as soon as possible.


Axles, a vital component at the bottom of your vehicle, are another potential culprit. They have a firm texture and are hardly damaged except for severe accidents.

Once it does, your car moves side to side at high speed.

Bring your vehicle to a professional service to regain stability and balance. But I need to remind you that the price is pretty costly.


If your car feels like driving on gravel, it may result from engine components. Many scenarios can happen in this situation.

There are many things to inspect to ensure your engine is working well, such as the fuel supply section, gasoline filters, spark plugs, etc. Thus, having regular checks is highly recommended.

Rear Spoiler and Body Kits

Rear spoilers and other modifications may affect your vehicle’s performance if they are cracked or fitted incorrectly, causing aerodynamic airflow.

When the back end of the car feels like it’s swaying, removing the rear spoiler may help.

Adjust or remove any additional body kits if you think your car rocks side to side because of them.


If you’ve checked all the components above and there’s nothing wrong, you may wonder, why does my car swerve at high speeds? 

Sometimes the problem does not lie in your vehicle but in the condition of the bumpy road.

The small smooth indentations, like trampolines on the road, can cause a shaky feeling. In this case, you’re free of worry.

Similarly, in the case of pulling, it’s mostly normal if your car feels heavy when driving.

What To Do When Your Car Feels Unstable At High Speeds?

back end of car feels like its swaying

The situation of your car moving side to side when driving can be solved by balancing the tires and changing the bushings and control arms.

If you’ve done those fixes, but the problem insists, bring your vehicle to a repair shop.

The mechanics will perform the check-up and give you a proper answer with a solution.

Change The Bushings And Control Arms

The control arms tightly connect the suspension with the front wheels, guaranteeing driving performance.

If the suspension is what causes a car to sway while driving, you can address the problem by replacing bushings and control arms.

Before proceeding with the replacement, make sure you purchase the detail compatible with your vehicle. Plus, identify the faulty suspension to save time and energy before starting.

In addition, you should prepare safety equipment such as safety glasses to protect your eyes from small particles and gloves to keep your hands clean while doing the job.

Balance The Tires

If your car feels floaty after new tires, it means the installations have not been done as expected. Rebalancing the tires may help, and I always do it myself to save money.

Here’s what you need to prepare:

  • Heavy-duty glue
  • A lug wrench
  • Small weights
  • A screwdriver
  • A piece of plywood
  • Portable wheel balancer

Below is the simple guideline to help you balance tires yourself:

  1.  Use the lug wrench to take out the faulty wheels from the tires.
  2.  Put the portable wheel balancer’s base on the plywood. Then, place the rod and balancer on the base.
  3.  Make the balancer’s bubble level.
  4.  Balance the wheel assembly by adding extra weight to it.
  5.  Do it until you’re satisfied, and use heavy-duty glue to stick those weights on the wheel.
  6.  Install the wheel assembly back to its position again.

Go To A Repair Shop

Bringing your vehicle to an auto shop is ideal when you can’t determine the root cause of your issue. Professionals will diagnose and conclude why your car moves side to side when driving.

As a result, you will get rid of the problem without spending too much time and energy. The cost of fixing varies, depending on what part is broken and what solution to take.

The Bottom Lines 

why does my car swerve at high speeds

Your car feels unstable at high speeds. This circumstance can cause the unpredictable performance of the vehicle, leading you to face the risk of an accident.

I highly recommend you solve the issue as soon as possible. Going to a repair shop is the fastest and most time-saving way to deal with it.

Leave a Comment