ok on my 92 hijet jumbo cab, is this a diff lock that is vaccum operated, or is it a 4wd actuator. its bolted onto the righthand side of the differential and the right hand cv shaft comes out of it to the wheel. When you depress the 4wd drive switch it engages, when you shift the transfer into low range it engages automatically also. have not checked to see if it disengages in certain gears or not. this is on a 92 or 93 daihatsu jumbo cab. Hey also heres a pic of the rear u-joint part number off the napa box, they had it in stock. the part number is 410 in case you cant see it on the box. Dave p.s. My 97 jumbo cab daihatsu does not have this type of actuator on it? why is that?