I have an Active Aid self propelled shower commode chair that has sticking front wheels. They roll only when they choose. I removed them once to see if I could clean the axles and housing and relube but yhe axle pins are not removable. So I sprayed them food with lubricant and they worked OK for a little time. Wife cleaned the large wheels of the soap scum and now they spin at the least little resistance, like the grout lines. Whatever she used did too good a job and left the rubber super slick. Any ideas on the front wheels?