2007 Hyundai Elantra Sounds Rough at Higher Speeds

My husband and I noticed that my Hyundai Elantra (2007) sounded rough when running over 60mph. The car has 61,000 miles on it and is due for an oil change, a radiator flush, and a fuel filter replacement. My manual says that the platinum coated (versus iridium coated) spark plugs would need to be replaced at 60K miles. I was told that the car would run rough at lower speeds if it was the spark plugs.

Based on the information I provided, does anyone have any ideas about what the rough ride at higher speeds would be pointing to?

???

Rough ride, as stated in the last sentence?
or
A rough sound, as stated in the title?

If it is a “rough” sound, please clarify what that means, and try to localize the sound for us.

The sound is rough and in listening more closely today, there seems to be shaking in the back. When I opened the rear windows, the the shaking sound was loud, but not when I closed the back windows and opened the front windows. Could that be a back suspension issue?

Opening the rear windows and hearing a “rough” sound could simply be the “cavitation” characteristic that most owners of modern cars have noted when opening the rear windows. This is due to the aerodynamic qualities of newer cars, in the interest of improved fuel economy. When the rear windows are opened, this disturbs the vehicle’s aerodynamics sufficiently to produce unpleasant noises and unpleasant sensations in your ears.

So–we are no closer to having any real idea of what the car’s problem actually is.
It could be a case of unbalanced rear wheels, or it could bad wheel bearings, or it could simply be the “cavitation” sound mentioned above, or it could be a whole host of other situations.

Noises are frequently impossible to diagnose via cyberspace.
I really think that you need to have your mechanic check into this noise complaint on the next visit, when he takes care of your maintenance. It might be nothing, but it could be significant. Make sure that he rides along with you so that you can demonstrate the noise problem for him.

It could still be the plugs. First rule of problem solving: get everything up to date before assuming you have an actual problem.

And, if these are the original rear tires, it could be the tires. When they get worn down they can make a rumbling sound even if worn evenly. If the have developed irregular wear pattersn, they can rumble even louder.

Lightly brush your hands over the rear treads to del for any anomlies. Also look carefully with a good flashlight aiming across the treads so it throws shadows. Post back withe the results.

By the way, I’m not disagreeing with VDC. A shop needs to give it a look-see. I’m just adding some suggestions of common rumble producers on cars with your mileage.

Excellent points, MB.

That’s Hyundai :wink:

It sounds like (and feels like to you) that you could have a tire wear problem in back. The problem could be caused by a defective tire or one that is not balanced correctly.

Is the noise a roar or rumbling sound ?

How old are the tires and when were they last balanced and rotated ?

CSA

The back tires were replaced in the fall. I’ll have them look and try to replicate the problem when I go to get my oil changed and coolant flushed. I’m gradually getting things done because I’m in the job market and doing a little part-time work.