im hearing a howling sound, coming from the front at 75+mph....its not super loud, but noticeable when the radio is off.

axles? wheel bearings? tire noise (probably not)?

 

I have a Cadillac that does this. It is caused by the rivets holding the fan shroud down getting worn and allowing the air flow in the cowling area to lift the edges of the shroud. The gap in the shroud acts like a whistle.

 

Most likely tire noise, or something more serious.

 

I once had a continuous droning noise on a Rover 75 I once owned. It was particularly noticeable on continental autoroutes and autobahns where high speed cruising is still possible. I, too, thought about wheel bearings, but in the end, it was found to be the set of Wanli tyres I had had fitted some months ago. I hadn't noticed the noise in England as I did very few motorway trips, it was on a holiday in Europe I first became aware of it. The problem after that was the tyres gave all impressions of lasting for ever !! In the end I dumped them, even though they weren't worn out as I just got fed up with the drone.

 

What kind of tires are they?

 

Michelin AS3+

 

My Dunlop SP Sport Maxx GTs (the OEM summer tire) got really noisy when half worn, a noise which began at 30mph and continued up to about 65. They were pretty quiet above that, so cruising at 75 was fine.

I just replaced them with Michelin AS3+.

The Michelins are very quiet at every speed up to 70mph, then there is a faint hum. It's not bad though, and I would take them over the Dunlops any day. Also the flat spotting, tramlining, and vibration around 55 mph, all present with the Dunlops, have gone away. The Michelins ride better too.

I really like these Michelins.

 

carzaddict, if you want to try and rule out the wheel bearings, a simple check that I have found is you get up to speed and when you have no one next to you, do a quick lane change. You want to get the body of the car to lean a little bit. You may even be able to get it with a bend in the highway and doing a turn to the other lane on the inside of the curve. What you are wanting to do is to do this lane change in both directions. If you hear the noise change when you turn one way and not the other, then odds are, you have a wheel bearing going and it will be on the side that you are turning to that the noise goes away on.

But, like others, it is most likely just the tires wearing and developing a little bit of a hum. I am starting to notice this with my car and mine is probably compounded by the fact that I have a little bit of feathering of the tire edge due to a bad strut in the front.

 

I've been on a number of Jag track days where I've driven the XJR and seen it belting around the track at speed, sometimes over 200kph.

One thing I always noticed watching them on the track is that they have a peculiar noise at high speed which I think is the air disturbance, it actually sounds hot, like a sizzling, crackling noise. Sounds awesome, like nothing is going to stop them.

 

Thanks guys, makes me feel a little better about the noise, im starting to suspect it to be tire noise as well because it changes as I drive over different road surfaces.

will try that lane change trick next time im alone in the car