Here's a you tube video of it
https://www.youtube.com/watch?v=73rpa9Tg7TE (https://www.youtube.com/watch?v=73rpa9Tg7TE)
started very faint about 2,000 miles ago and has progressivilly gotten louder
car has 85,000 hard miles on it been running the LMS 93+ tune since 10,000 miles
much spirited driving and mutiple 1/4mi track passes 13.4 best time
Tires have about 7,000 miles no odd ware patterens
had the alignment checked today all good
sound starts from a roll and gets louder the faster you drive
sounds like its coming from all 4 cornners
rear dif fluid never changed
PTU unit fluid never changed
Has anyone else expierenced this ?
That's a crazy howling noise, which is usually caused by a wheel bearing. But they don't normally start making that noise from a roll. Only once up to speed.
The odd thing is you stated it sounds like its coming from all 4wheels. Does it change in frequency or noise level with any steering input?
The drive shaft does have a bearing in the middle that supports it.
I would change the fluid in the RDU and PTU first.
Then see if anything changes. Its waaaayy past due to be changed anyway.
I had a pulsing vibration nowhere near that loud
that would start around 45mph and quite down around 80.
Was finally fixed by replacing the RDU.
When did you change tires? I had a car that did that once, crazy loud humming. turned out the cheap tires were the cause
Please don't think this is an insult, but are your tires directional. If so, they may have been mounted wrong, and installed wrong.
If they are not directional, have you tried rotating them to see if the noise changes?
Cupped tire?