140h diff lock troubles

Hello all, I am experiencing some troubles with the diff lock on my machine 140h, first thing I noticed was a fuse blown on my diff lock switch, which never happened before, when I backed out of the shop and slightly turned, the rear of the machine started to skip jump on loose gravel like it was locked up and you were trying to turn on pavement, no diff lock light on , so this is when I noticed the fuse gone on the switch, replaced the fuse every thing seemed fine then the fuse blew again and it acted like it was locked up on pavement again, the rear pass side really jumping, pulled back into the shop, this machine never acted like this ever even when locked up on gravel or hard packed road, our mechanic replaced the diff solenoid and also took a pressure test at that port its at 220 at idle he feels that's to low, its also leaking oil out the back of the trans by the 3 bolt plate( lower one), replaced o ring, still pushing oil out, also checked tandems all is fine there, any idea's what's going on? thanks :Banghead

140h diff lock troubles