howling/humming sound above 20 mph

[henduford]

I have a 2004 4 Runner sport edition with the v8. I have 107k miles on it. I have been having a pretty loud humming or howling sound as I increase my speed and it usually starts around 20 mph and higher. It doesn't seem to be rpm/engine related but is more speed related. At first I though the new tires i put on it were causing it but i can hear the tire sound separate from the other howling i'm hearing. Any ideas what it could be? It also does it as im decelerating and stays loud as i get below 20 mph until i am almost stopped and then it stops.

Any help would be much appreciated!

 

[Troymclure]

My guess would be a wheel bearing. Just went through the exact same thing on mine.

 

[M1911]

My guess would be a wheel bearing. Just went through the exact same thing on mine.

Yup, me too. Mine was the right front wheel bearing.

 

[henduford]

How much would it cost to fix? Is it easy to do, or would i need a shop to do it?

 

[fdbyrne]

On the 4th generation 4runners it's cheap and easy. They both on as opposed to being pressed in like the 3rd generation.

Typically you can serve back and forth in long sweeping turns and the sound will stop and start as your vehicle rocks.

If it's not a bearing it may actually be the alignment.

 

[henduford]

Yeah, if I swerve to the right the sound goes away. It sounds like its on the drivers side front wheel. Are there any special tools needed to do it? If it just bolts on, I'm assuming not, but thought i'd ask.

Thanks for everyones thoughts

 

[fdbyrne]

If it goes away when you turn right, it's probably the passenger side bearing. When you turn right the truck rolls left taking weight off of the passenger side.

The replacement procedure isn't hard. There's a writeup on here somewhere. You're biggest problem will probably be stuck bolts. Mine were rusted on pretty good. I had to cut a few off with an angle grinder.

 

[fdbyrne]

As far as tools go all you should need (in theory) is a handful of sockets, a torque wrench, etc. A compressor, air ratchet, and breaker bar would be really helpful.

Find that writeup on the process and it'll make a lot more sense.

 

[awdjunkies]

As far as tools go all you should need (in theory) is a handful of sockets, a torque wrench, etc. A compressor, air ratchet, and breaker bar would be really helpful.

Find that writeup on the process and it'll make a lot more sense.

Here's a quick video : https://www.youtube.com/watch?v=BVuM8iVO6u8

 

[henduford]

Awesome thank you everyone for your help! So it sounds like its the drivers side but if when I turn right its most likely the passenger side, is there anyway to actually know or will I be able to tell if its bad before I start on one side and it ends up being another one?

 

[fdbyrne]

If it goes away when you turn right, it's almost certainly the passenger bearing. Sound waves bounce around and make you think it's coming from one direction when it's really coming from another. They may both be bad to be honest, but from your description my money is on a bad passenger side bearing.

When mine went on my tacoma I didn't get the distinctive sound. It was pretty obvious however when I pulled off the wheel, caliper, and rotor then spun the hub by hand. It took a lot of effort and had a gritty feel.

 

[hullinger]

Just thought I'd share my experience with my '04 4runner. This past fall I first noticed a slight vibration coming through the turn signal and windshield wiper stalks. It wasn't obvious unless I lightly placed the tip of my finger on the stalk. The vibration started around 35 MPH or so and I just dismissed it as a tire problem. About a month ago I started getting the hum that would go away on long sweeping right hand turns. This weekend I jacked up the truck and turned the wheel by hand while holding the coil spring and couldn't tell for sure if it was a rough bearing or the light drag of the caliper. Once I pulled the caliper off could I than feel and hear the bearing grinding. It wasn't terrible but it was there. I ordered a new hub and bearing from my parts store today and had them press them together along with a new seal and reuse the four bolts. I did the install using the earlier posted Youtube vid and now the hum and turn signal stalk vibration is gone. It was a fairly easy job, but like everything I do, it took me twice as long. The hardest part was getting the hub off as it was crusty and stuck on pretty good. A bunch of hard whacks with a big hammer got it loose enough to pry it off all the way. I'm glad I did it myself and the Youtube video gave me the confidence to do it.

Chris

 

[henduford]

Thank you everyone for the help! I am going to tackle it today with my uncle who was a mechanic for 25 years. So hopefully with his help it should go smoothly. I'll post my experience after i am done.