Well after putting around in the beast for the last 12 months i thought i'd better let my automotive class have a look at the fluids left in the ute. Between the diff and the 4 speed manual box they were able to drain around 1 litre of oil. Diff took around 1.2l to refill and the gearbox around 2l. The magnetic drain plugs were clear but the oil wasn't that good, it flowed but jeez i'm glad we changed it.

For the $50 worth of oil it is well worth spending 1 hour of your time doing this sort of maintenance.

Tomorrow I'll let them fit up a new exhaust.