Funny you mention this. I just had mine appart over the weekend to clean and adjust the crossfeed nut. I have the standard 4003, but id imagine they are similar if not the same. There should be a capscrew on the nut to squeeze the slotted half together. I tightened mine a tiny bit to take up some backlash and still keep it smooth. I still have backlash, but much better.Im about .010" backlash. While I was at it, I cleaned and scotch brighted the gibbs and adjusted everything. Works good.