I'm not sure if this is normal or not, but my differential whines fairly loud when it gets warmed up over 50mph, when i press the clutch it goes away, is this normal noise or is there something going out? I know these 10 bolts are terrible to begin with. I'm not sure if it has a gear set in it or not i got it slightly modded and the build sticker is missing.

 

if it goes away when you push in the clutch its not the rear end, thats still spinning.

 

Actually B.C. yes it could be, because the r&p gears aren't under a load with the clutch disengaged.
Probably would be a good idea to know what kind of gears you have, just in case they were ever swapped. Some aftermarket gears make noise naturally. Maybe it's time for a routine oil change anyway?

 

ya didnt really think about the load... learn something new every day

 

A gear oil change and then we will see.

 

How do i tell what gears it has, is it stamped on the ring somewhere?

 

Like 69 said some gears are noisy but whine can also be an indication of improper adjustment or gear wear, also bearing noise too. When you remove the cover to change the fluid inspect the gears and see what they look like. See if you can find a backlash spec. in a service manual or online and check that too, if there is no obvious gear wear. To inspect the bearings you would have to disassemble the rear end.

 

The old timers I know always said if you lift the gas from light throttle and the noise goes away its usually gear noise if it stays the same its usually tires or axle bearings, by turning left and right you can usually figure which side if it is bearings. Just and ole rule of thumb that has worked for me.

 

Is this a new car to you? new noise? Getting louder?

 

lol.... Gorn, you got suckered into an almost year old thread!