Noise similar to tire/road noise. Worst at 65+mph.

So I started hearing a new noise this week and need some ideas.
It varies with speed but not RPM. Turning doesn't change it. Handling and ride still feel normal (no slop or wandering).

Under 30mph, I don't really notice it.
At 30-60mph, it just sounds like tire noise that you'd get from an offroad tire. I have street tires and this noise is different. Radio at normal volume is usually enough to drown it out.

Over 60 mph, start hearing it more and at 65mph it sounds like I'm following one of those crappy riced out Hondas and there is slight vibration in the floor. A buzz or hum might be the best description. It continues like this up to 70mph. I haven't gone over 70mph.

I can't figure out where exactly the noise if coming from since it's only at speed.

Things I've changed recently before the noise:
1. New brake pads but noise didn't start until about 1200 miles after installing them.
2. Drain/fill rear diff. Used same oil as last time. Did this about 2 weeks (~800 miles) before the noise started.
3. New rear engine mount (at tail of transmission). OEM part from dealer. Installed about a week (~400 miles) before noise started.
4. Greased u-joints about 1 month (~1600 miles) before noise.

Things I've tried to see if the sound changes or to see if anything feels odd:
1. Changing lanes or taking long curves at speed. Didn't change the sound at all.
2. Shifting into N (auto trans). No change in sound.
3. Slow figure 8s in a parking lot. Didn't feel any slop in the steering or hear any popping sounds.
4. Driving around the yard and in the woods to flex the suspension. Didn't hear anything odd.
5. Greased u-joints again. No change in sound.
6. Checked tire pressure. 32 psi all around as usual.
7. Braking hard from ~60mph. Feels normal. No vibration or anything.
8. Accellerating lightly vs aggressively from 40-70mph. Hear it more under light accel but that's only because I can't really hear it over my exhaust.
9. Taking foot off gas at 70mph and coasting down to 30mph. Same as usual (loud buzz until I get around 60mph, then seems like road noise that gets quieter as I slow down).
10. Driving 65mph in overdrive or regular. No difference.


Anyone have thoughts?

 

wheel bearing

 

No additive. Same oil I used last time I changed it. Didn't use additive then either. Valvoline "high performance" 80W90 says it doesn't need additive. Local dealer uses same stuff without additive.

 

Cable tie around drive shaft?

 

Wouldn't turning cause the noise to change if it is wheel bearing?
Didn't feel any play when I had it on the jackstands today.

Could the driveshaft be out of balance all of a sudden and just hitting a harmonic or something around 65?

Maybe I can put the old rear mount back on so see if the sound goes away. Maybe it slightly changed my driveline angles.

 

Best way to isolate a tire noise is , to drive on a smooth road surface that changes from concrete to asphalt. If the noise changes between sufaces, it's tire noise.

 

Haha I was joking about the drive shaft cable tie.
Try rotating your tires and see if it changes. Just a cheap thought.

 

My usual tire noise changes based on surface but not this other new noise. Calling it tire noise is just the closest description I could think of.

 

Best way is to raise the vehicle, put it in drive, and use a sethoscope to find the source of the noise...

 

Good question for the OP...

 

Yes. LSD. Sticker at fill plug.
Like I said though. Same oil I used last time (40k miles ago). Jug says "limited slip" on the front of it.

And though I don't generally trust dealerships, the service guy a couple years ago said this is the exact same stuff they use and that they don't use additive with it either.

Would it hurt anything if I put some additive in though just to rule out the possibility?

 

I've had various unexplained noises for the last 120k miles. This is just a new one. My usual approach is try a few things and if nothings works, leave it til something explodes so I'll know what to fix. Nothing has ever exploded though.

I'll swap the old rear mount back on tomorrow and test drive to parts store. If noise is unchanged with the old mount in, I'll get some LSD additive.

 

If the noise is present driving straight down the road then the LSD clutches / lack of additive is not your issue. If the problem only occured during turns, then, yes, but I'd still through in some additive anyway.

Inspect the carrier bearing. I'm assuming you checked the u joints carefully when you just greased them, if not, slap yourself and go do that too.

Rotate tires and see if there is any change.

If nothing conclusive there, my bet is on a wheel bearing as well, though it might be a rear one if turning isn't changing the noise.

 

sub'd. I discovered a similar noise in my truck today, mine kind of pulses though, thought it was tire noise but the pulses are waay slower than the tires rotation. the noise starts around 34, 40 mph.

 

not sure where you live, but i am in louisiana where temp. fluctuates as much as 30+ degrees some days.

I assume you had 4 wheel alignment done, balanced tires, etc all the normal stuff. i HAD THE EXACT some problem on my 2005. I started hearing that same thing, I have stock tires, but at times it sounded more like when I drive one of the trucks with off-road tires. I changed the U-Joints, when I pulled the old ones out they were pretty worn, so i figured AH-HA! fixed.

WRONG! I couldn't figure it out for a long time, sometimes it was pretty bad, sometimes not so much.

For me anyways, i figured out it was tire pressure! When we had big up and down temp. fluctuations it would get bad.


if you live where temp goes up and down pretty severly alot, keep a pressure gauge with you and start checking tire pressure every few days especially when the weather is crazy.

hope that helps, it worked for me


cheers,
disco

 

great advice BTW! i forgot about carrier bearing, get under it and grab where the u-joint is right after the carrier and the front driveshaft before the carrier and shake the hell out of it, it will have some up/down/side to side play from the bushing of course but what your looking for is actual play or even clicking sounds or 'rough' 'feeling' kind of play i guess you could say. another idea would be the carrier bushing, just to be sure give it a good look over and make sure its not getting worn. dont know id OP said he has a 4WD or Prerunner, but prerunners dont't have ANY grease points until you change to parts to the ones that have grease points, which is completely outrageous in my opinion!


cheers,
disco

 

Tire pressure has stayed steady.

Bearing and u-joints were all changed spring 2012.

I noticed there is some play where the driveshaft goes into the transmission. I don't remember noticing that slop there before.

 

up by the transmission? is it side to side or in and out in reference to the drive shaft?

cheers,
disco

 

My vote is the carrier bearring.

I've never been able to "feel" the bad carrier bearring. All the times I changed them, I could feel no slop or rougness in the bearring. The only way I could tell they were bad was when I cut them apart with a grinder thin disc. It was always the chrome on the race had delaminated.