Transmission slipping in reverse?

[Tim Mason]

Recently I noticed that my transmission is slipping in reverse? No notable issue in Drive.
2002, well maintained, 175k. I tightened up the servo valve several years ago during a pan drop/filter change. Royal Purple fluid and regular filter/oil changes. Any ideas before I have a shop check it out?

 

[Paul Fithian]

I had a similar issue, weak reverse, all other gears were fine.

I replaced the valve body with a Shift-Rite, now it works like new.

 

[EddieS'04]

Paul may have a good point on the valve body. As far as a pan drop and fluid. I would not have mixed the royal purple with the motorcraft mercon 5. Most of the fluid is in the torque convertor. When I do a pan drop on my '04 I go back with the motorcraft merc5...

 

[Paul Fithian]

Use only Mercon V in the 5R55E transmission.

 

[EddieS'04]

Use only Mercon V in the 5R55E transmission.

DITTO, mercon v or mercon 5, same stuff. I prefer to stick with the motorcraft brand.
I have a tune on my trans plus I manually turned up the epc. No problems yet.