Jerry,
I lubed the chain once in awhile (less than once a year) with a spray chain lube that was not a white grease version. The slide frame itself was made of angle iron and you may find metal to metal surfaces contacting as things age. Wherever I have metal on metal contacting and movement of the parts I like to wipe on a little Super Lube clear grease with Teflon. You can get a little tub of it on Amazon. It is not messy and my slide seemed to go in and out easier.
Later Ed
