Hey guys, I've been researching this trying to find out answers but haven't found a definite answer yet. So I drove from Seattle to Portland couple months back. Before the road trip, sure the car has road noise but I was still able to hear my phone conversation using my earpiece fine or I don't need the radio on full blast just to be able to not hear the road noise. After my trip, the road noise is just REALLY loud now. I can no longer hear my phone conversations, have to have the radio on really loud just to get rid of the road noise. I got the differential fluid changed, tranmission fluid change, and engine oil changed again after the trip. After reading through a lot of posts that might be the cause, it could be transmission, rear differential, or wheel bearings. What are your thoughts?

 

How old are your tires? One or all of them could've worn down enough to the point where there's no sound protection left in the tread.

 

Road noise is the sound of the tires rolling across the surface of the road. It can be affected by the tires, the composition and smoothness of the road surface, and the amount of noise insulation in the car. You can knock the insulation off the list of suspects because you probably haven't removed the carpet or damping material from the floor. If you are driving the same roads as before your trip, you have only one suspect - your tires. One of the marks of a good tire is that it is quiet when rolling. As tires wear, they can become more noisy, especially in the case of cheap tires. Bad alignment can wear the best tires such that they become noisy. You should have your alignment and treadwear checked.
You named the transmission, diff, and bearings as possible culprits for your noise. These parts do not make the same type of noise that actual road noise does. Usually when mechanical parts are failing, there is an associated vibration. Are you having vibrations as well?

 

Thanks for the reply guys. No there isn't any vibrations as of yet. It's good to know that it isn't tranny, diff, or wheel bearings. I got my new tires at 93K miles and now i'm at 118K miles. The front tires look pretty good but the 2 rear are getting worned down. No visible threads showing yet but looks like I'll need to replace those pretty soon. I'll have to get an alignment check as well. At least I know it's nothing major. Thanks guys.

 

It is hard to diagnose without more data but without clear mechanical sounds it is easy to focus on road/tire noise.

Here in the PNW studded tires are legal much of the year so many roads are paved to take the abuse making the surface extremely rough and noisy. I find the roads up here produce more noise than anywhere else in the country. Look for some smoother surfaces before you make any decisions.