hi is it a simple job to change the oil and filter in my auto box . the box works fine with no problems . ive had it for nealy 3 years and done about 24000 in that time i can tackle most jobs on a disco ie swivels timeing belts head gaskets ect(not on this 1)on 2 i had before but this is the first auto ive had so any advice would be helpfull thanks