99 Bravada

I have a new whine

When the engine is running I hear nothing but the purr of the motor - I put it in drive and I hear what sounds like low PS fluid. Back in park it goes away.
Trans fluid is full - what else should I look for? Cant lose my favorite ride

Thanks

How many miles? Has the trans fluid & filter been changed?

Sorry - about 140,000 miles. Trans fluid and filter changed about 2 or 3 years ago (less than 20000 miles)

No whine in park or neutral

No whine in park or neutral

try leaving it in park turn on the A/C, press on the brake pedal as hard as you can and crank the steering wheel back and forth to see if any of those are responsible for the whining.

I do not notice any noise when the vehicle is in neutral. I turned the A/C on, put it in park and turned the wheels to full lock and no whine, but as soon as I put it in Rev or Drive the whine starts

I'm weak on transmissions but this doesn't look good for yours.
I'm guessing front pump and shop time.