Amer

Hi a little background about the car, it has 17,000 miles and is stock.

The problem I get is when I turn the wheel (doesn't matter left or right) all the way till it locks and accelerate slowly in 1st gear and I hear a humming noise inside the cabin, I can't tell if its coming from the front or rear of the car.

I tested if it was my steering, so I accelerate slowly and put the gear in neutral and turn the wheel all the way till it locks and the humming noise isn't there.

Anyone think I should check my differential for damage? get the diff fluid changed?

xviper

I would have guessed it was your LSD but then you put in that part about the steering and no noise. If it was the steering, you should be able to crank your steering full lock (do it on a loose surface) with the car just sitting there and still get that noise. The fact that your second test was uneventful, would tell me to devote your attention to the diff, but do my test to see what you find. Try changing the diff fluid with a known fluid that has proven history. For all we know, your car may have always made this noise under those circumstances and you just now noticed it.

Amer

It's definitely not the steering wheel, my 2nd test proved it. What gets me is when I accelerate is when I get the humming noise.

Will dirty/worn out diff fluid make this noise?

xviper

Your LSD is supposed to "slip" when you go around corners, but if you accelerate just enough, the LSD will try to lock and in some cases, completely lock up and cause the inside to squeal. You are likely going at just right speed and amount of acceleration to make the LSD "try" to lock but won't.
It wouldn't hurt to change the fluid anyway. When was the last time and what did you use? Test it on a sandy road surface and take off aggressively. Does the rear lock up and give you two equal tire marks?

Amer

xviper, I made the mistake of not getting previous service records from the 1st owner. As far as I know he hasn't changed the differential, I bought it from him at 6,000 miles and right now it has 17,000 and this is all within 4 months, I'm definitely going to have the diff fluid checked.

xviper

It may be nothing and I don't wish to alarm you, but it's been reported that a dealer putting in the wrong fluid has resulted in a hum. This led to the diff being toast. When you change it out, at least smell it and document how much stuff is stuck to the magnet. Take pictures. The oil fluid should stink like bad farts.