I have a 1997 silverado, I just recentley bought. It just has started making a whistling noise while In low gear. Its a automatic, I put it on jack stands, ...

I have a 1997 silverado, I just recentley bought. It just has started making a whistling noise while In low gear. Its a automatic, I put it on jack stands, took the drive shaft out (Its a 2 peice) and turned the one peice left in the transmisson with my hand fast and can still hear the whistling noise?

It only does it when I get in the gas until it changes into higher gear, any idea what this maybe? It dont seem to hurt when I drive it just gets on my nerves......Thanks alot for any help.

My guess alumimum metal in transmission rubbing very lightly... My guess would be the Lo/Rev casing is cracked or warped... It is known with age and heat. Also, maybe the Sun Gear Shell is flared to age and heat. How many miles do you have on this Truck. If the performance and operation is not effected, just drive it to rebuild time... All info from ATSG 4L60E manual

Well the lo/reverse pistion was weak back in the early 80's they dont warp iv seen one crack in a 700r4 early trans only. That was a miss print in the atsg manual. My guess would be the low/rev planet is pitted and needs replaced. If you dont all the metal will start hanging valves and solenoids. Take truck trans shop have them check it out.

Truck has 193k on it.

Thanks