detecting whine

[xvr843]

How can I detect a transmission whine? Rev in neutral?

[MattStrike]

Usually, if you can't hear it already it's not whining. It will be loud enough at idle to hear. It gets louder at higer RPM as well, so if it's not already it will get audible at/near redline. What does your fluid look like? Trans fluid should be changed every 50k-100k depending on how hot the fluid gets. It should be red (not brown or dark) and not smell burnt.
The trans can whine if the fluid is bad/going bad. The bad fluid leaks past the seals easier, and can cause low pressure.
The pcm commanding 'max line pressure' to the trans is another reason it can start to whine (usually caused by leaky seals or bad fluid).