hey all you tranny gurus:

after the last couple of road trips ive been on, my trans behaves oddly:
I will have been driving at highway speeds for hours, only going
forwards and only slowing for hills or stopping for gas.  then when i
put it in reverse, the van bucks/lurches while i am trying to back up
and the transmission is ringing/clanging loudly in harmony with the
lurches.  (this happened last night, again, at the end of a 9 hour
interstate drive).  It seems that after the engine/trans totally cool
down it operates ok:  this morning it drives just fine, forwards and
reverse.

the syncro 4wd 5spd trans and clutch have approximately 55,000mi on them
and i am running Redline MTL (75w-90)

does anyone know what this problem is???

thanks,
fred