alot of times it wont set a code, occurrence is too brief. very common on gm's also. pull the abs fuse or set a hard code(so abs light is on) and see if problem goes away. or if you have access to a scan tool , can sometimes see it happen in whl speed data. just creep along at very low speed(5-9 mph) problem sensor will not match others if 4wheel abs, or will see it drop out. note, some systems don't drop lower than 3mph in scan data, I cant recall if its gm or mopar