Give us a bit of a re-cap on the history and what is the trans used for?
Low/reverse clutches are only used in manual low gear and reverse. They are more or less a non-shifting clutch. They only have to release coming out of 1st, and apply on a manual 2-1 downshift.
If you are consistantly hurting the L/R pack the first thing I would check is clutch pack clearance.
The second thing I would look for is a crack or porosity in the case in the low passageway area (near the rear of the VB
, but check the entire case). Also check the VB
for any modifications or problems that could cause a crossleak.
My next thought is that maybe you have some type of dual feed of the directs that is backfeeding low gear. Possibly a bad center seal in the direct drum or sealing ring on the stator.
Tell us more about the trans,
what mods, etc.