98 Buick Regal LS Transmission Problem - New Issue

I have had my PCS replaced and my tranny shifts fine now. But the new problem is when you have the car in park or in reverse(dosen't do it in drive) the tranny is making a funny noise, kinda like when you dont have any tranny fluid in it after a fluid change if you know what im talking about. A ratteling like noise coming out of the tranny. The mechanic said it sounds like to him a bearing rattleing in the valve body. He said it might be a faulty PCS and he said he would warrenty it, but just drive it a couple of days and see if it goes away. I just want a second opinion on the matter of what the problem might be.
Thanks

Was the PCS solenoid GM/AC Delco or an aftermarket brand like Sorensen? If the rattling was not there before the bad PCS solenoid was replaced then I'd take it back to him under the warranty.

The pcs is an genuine ac delco part, is seems as the noise has quieted down, i wait and see if it goes away completly. If it dosent in 2 weeks then i will take it back to him. Does an ac delco part have anything to do with it?? I know ac delco parts are better quality, but would that make a difference.
Thanks for the quick reply.

Hopefully it settles down. After getting tranny work done mileage needs to be accumulated to see the full extent of the repair job. The PCM has to relearn. Adaptive shift points, etc.

Based on your year model probably not. The AC Delcos are prone to failure like the aftermarkets. Now around 2002 it changed. GM came out with a newly designed PCS solenoid but it is not backward compatible so it wll not work on '98 models. The new PCS was fitted to the 2003 model year Regals.

The computer might have you still in max line mode this would make a buzzing sound. This should work its self out with the TAPS.