transmission Powershift transmission--funny sound

[Alan Blalock]

I have a 1964 Avanti 3 speed flight-o-matic. I just changed the pan gasket and added fluid. The gears engage,but when I put the selector in either park or neutral the transmission makes a strange sound like "chirping" or a suttle low grinding like noise. When I return it to drive drive or reverse the sound stops!!!!!!!!!! Anyone have an idea?

[studegary]

Buzzing usually means low on fluid, but I do not know about the noises that you describe.  What type of fluid did you use?  Is it the same as what the majority of the fluid in the transmission/torque convertor is?  

[mfg]

1 hour ago, Alan Blalock said:

I have a 1964 Avanti 3 speed flight-o-matic. I just changed the pan gasket and added fluid. The gears engage,but when I put the selector in either park or neutral the transmission makes a strange sound like "chirping" or a suttle low grinding like noise. When I return it to drive drive or reverse the sound stops!!!!!!!!!! Anyone have an idea?

The buzzing sound is coming from the Powershift's pressure regulator....It's an indication of insufficient fluid , or the transmission pressure control rod is improperly adjusted. (too long)

[brad]

Many times it rears its head when the mounts get all worn out. 
Make sure they are in good shape, and the transmission hasn't settled. Also make sure the spacer is under the drivers side mounting stud. If the trans has never been rebuilt previously use type F fluid. If it has been rebuilt then most likely it has the later replacement "paper" clutches, and requires Dexron.