Hey all, I'm hoping to get a little insight from more knowledgeable folks here, so thanks in advance for taking the time to read my post!

My 2006 Sonata GLS (132,000+ miles) has been having a problem the last year or so that seems to come and go in severity... there is a vibration that can be felt throughout the car at all times, but it becomes more obvious when I press on the brake pedal. If I drive at higher speeds (80~90 mph) for a minute or so, the vibration is even more intense when brakes are applied. However, the higher speeds themselves do not seem to make the vibration any more noticeable than it is at lower speeds.

When I first noticed the vibration last year, I got a 4-wheel alignment, and then the next day went and bought a new set of Goodyear tires, but the vibration remained. (Although the alignment and tires took care of a couple other issues I was having.)

Another reason I am pretty sure it's in the rear is because if I'm going 60 mph or more, and firmly (but slowly and carefully) pull up on the parking brake and apply a little pressure, the vibration intensifies, but it goes back to "normal" when I put the parking brake lever back down. (I keep the release button held in while I do this so the lever won't latch.)

So, my guess is warped rear rotors, but I wanted some opinions from other owners on that hypothesis. The pads (Hyundai OEM) are fairly new and don't have a lot of miles on them as they were replaced a couple years ago.

Also, it's worth noting that the vibration is at its worst in the mornings after the car has been sitting out overnight, especially during the cold months. After I drive it about 15~20 minutes on the highway, the vibration dies down, but never completely goes away.

Any thoughts?

Thanks!

 

Take the wheel off and inspect the rear rotors.
Otherwise, take it to your best friend's place and have him do it ...hahaha

Got to get dirty if you want to find out the problem

 

Sorry, I didn't realize I was posting in the DIY forum. I don't have the tools or proper place to work on the car myself, and neither does my best friend. Thanks for the suggestion though.

 

Well, if you just want to speculate on what is the problem with your rotors then you can do that.
I just thought you wanted to do something about your rotors

 

For completeness: Only Y3 and earlier Sonatas have the parking brake operating on the disc via the caliper. Later ones have their own drum in hat for parking brake. Only joint element is the rotor. So pulling the brake lever will tell you about drum (in rotor) condition mainly, not much about rotor outer surface where caliper works on during normal driving/braking.

If vibration occurr in either brake subsystem however there is the suspicion that the dih-rotor is either warped or it hasn't been assembled well.