My 2005 Toyota 4Runner is the V8 version with 4 wheel drive. I’m getting a pulsating humming sound at around 70 MPH - woh woh woh. Thought it might be new tires but it stops the instant you let off the accelerator. Hard to pinpoint location but if I had to guess I’d say driver’s side front. Any ideas?
I had a similar noise in a 2003 4 wheel drive 4Runner with th V-6. My noise was caused by a left front hub bearing.
Can You Feel It At All In The Steering Wheel ?
Toyota published a 25 page TSB (Technical Service Bulletin) for their technicians to help them diagnose problems with Steering Flutter at highway speed.
The vehicles covered by the bulletin are only 2003 - 2005 4Runners.
They have a flow chart and drawings to help with repairs. First, you check tires. Then you keep trying other procedures, including replacing the Control Valve Spring and even the Steering Wheel, until the problem goes away.
The 25 page bulletin is # ST001-05. You’ll need to check VINs to be sure your vehicle is included in the bulletin. Toyota did these repairs under warranty for vehicles within 36 months/36,000 miles.
CSA
Thanks Triedaq and CSA. No problems with the steering.
Sort of sounds like a wheel bearing going out to me. But before you go down that road, do this one little experiment first. Next time you hear it, be sure all your windows are rolled ALL the way up. Did that change thesound or eliminate it? Sometimes you can get a sort of whoop whoop whoop sound which is hard to tell where it is coming from, but it is caused by a window not being fully up and the passenger compartment becomes a sort of wind powered resonant chamber, like the inside of a tuba.