Transmission noise in reverse

[TerryGlessner]

My 2007.5 with 68RFE at 127,xxx miles has developed a slight squeal/whining noise while in reverse. The noise is only noticeable when in reverse and in the garage, it can't be heard when outside or in any other shift position.
No other transmission issues otherwise. Any help would be appreciated.

 

[Hoefler]

2007 had the 48RFE, the 2007.5 had the 68RFE, could please you clarifiy the year and transmission so you will get the proper advise.