Whining sound while accelerating

Well now that I read it right, rear diff shouldn't be whining in neutral.

 

yea it's pitch increases with rpms.

 

How many miles? Could it be timing belt related? A bearing within the system? What oil and filter do you use.

 

i actually just changed the oil the day before this happend. I use Valvoline 10-30 and I put a phram oil filter [ i think i might stop using them i just like the grip on them].
It just turned over 118,000 yesterday. I think what did it is when i was turning around on a slight hill. reversing up the hill juicing it then abruptly stepping the clutch down and the break.
I also hit a terrible terrible pot hole going around forty. That massive jerking of the vehicle could have done something?

 

I wouldn't think at this point it's anything with the timing belt system unless it was just that time; in turn, nothing you did would have done this and instead it may have just happened.

For the OP he has an auto tranny. I don't know a lot about the 3.8L but could it be the cam whining?

 

OP (4x4Jim):

It could be dry u-joints. Get them lubed, or do it yourself (real easy to, but you need a grease gun + cartridge)

 

Mine does the same. Even after I did a full service and changed the serpentine belt as well, the wine is still there under acceleration.

Might be normal

 

i went to an off road center, and they said it was my alternator! the guy said it was normal to get the amount of miles out of the factory one mine still got. The off road place [midwest off road] said they cant get the factory brand so they'll have to get me and STP brand alternator. Any suggestions on that brand? I'd like a factory brand myself, but Midwest Toyota treated me like shit yesterday so I don't want to give them my money.
Thanks for everyone's helpful suggestions!!!!!

 

They replaced the alternator, and all of my idler pulleys needed to be replaced too.
I thought it was going to be around 400 now it's going to be closer to 650. Gosh darn it.

 

Did it fix the whine?

 

Yes is did but now there's a small amount of high pitched feedback in my speakers. How is this occurring? Can it be easily fixed?

 

Hmmm. Yes I have heard of this before. Did they replace the ground wire going to your starter?