Noticed a sort of rattle in rear end. Put rear up on jacks ran truck in second gear and noise seem to occur after accelerating just off idle. Checked and replaced oil in diff. While truck on ground checked whether there was play in driveshaft seem to turn 10 or so degrees backwards and forwards before engaging diff, if that makes sence. There seems to be more play than the front shaft, not sure if this is normal. Please note I am not a mechanic but will try anything with instruction. It dosen't have a diff locker.

Cheers Dazz