It depends on what is in the slide. If you have a kitchen cabinet look under the false bottoms or in drawer compartments.
If not look in the roof of the basement compartment or wheel well.
I have a 2002 Monaco Windsor with 2 slides. The large slide has 3 rollers, 2 are accessible from inside in the kitchen cabinet. The 3rd roller has to accessed from the front driver side wheel well, there is a plastic cover that protects it. I had to adjust my back 2 slides rollers to lift the slide up a little.
2002 Monaco Windsor 38 PKD
2005 Jeep Grand Cherokee w/5.7 Hemi