Either tires are worn out (cupping) or you got a worn out wheel bearing.

Does the droning noise change when having the car change load (i.e. making a slight right bend vs slight left bend)

 

The first thing to think about is if the noise changes with engine rpm, vehicle speed or other. If it's vehicle speed and the noise changes depending on the road surface, I would think about the tires. If so, you could verify correct pressure and rotate them - while they're off, do a visual on tread wear. Could also check alignment although you would expect to see that indicated in tread wear pattern.

Otherwise, if it's vehicle speed, I would think drivetrain.

Another thought would be exhaust. Visual inspection is good and, with car running , carefully feel for hot air movement. Particulary look at the flex pipe in the front where the downpipe tranisitions to the horiontal run.

Buckaroo

 

I don't think it is the wheel bearing as the usual increased drone when turning at speed isn't happening and the tires are my winters that I've been driving and rotating for a few years now. It's strange as it happens occasionally and I only notice because the car is usually silent on the highway and now it's just slightly louder with this drone/hum.

 

Tires usually get nosier as they wear. Road surface contributes as well. On the other hand, exhaust systems don't last for ever. My 08 V6 is louder than my low miles 14.5 SE V6, no leaks but the mufflers may be "wearing in".

 

I did notice some deterioration of the joint from the Y pipe flex to the midpipe but I don't think it is that sound I'm hearing. It seems to be most noticeable when I come off the gas and it sounds like something is winding/revving down in the engine bay. I can swap out my tires for a few days to rule that out.
On an aside, when the time comes, what can I do about the joint from the flex to the mid pipe. I imagine the full replacement would cost a fortune. Can I just weld in a joint there to preserve the rest of the pipes which are in good shape?

 

Can I just weld in a joint there to preserve the rest of the pipes which are in good shape?

Yes.

Buckaroo




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