I need to replace the filters in my MF135 and Ford 3000 (i know this is the wrong forum, but i think all oil baths are pretty much the same). When i remove the pan, i'm assuming its full of oil, which will require a balancing act to not make a mess. From the manuals i have there is a pre filter then a primary filter. I would like to replace both. I know it wont be cheap, but cheaper than a new engine. What oil do i need to fill it with. Also do i just pull out the pan (bath part) drain out the oil, replace the filters, refill with oil then install or am i missing something? I dont want to get out to the farm and not have a clue as to what i am doing.