Thiking of doing four gear spider mod. , but don't know what wt. oil to use.I hear talk of 1000,3000,5000 etc wt. I don't have a clue on what to use . I will be bashing most of the time, but there is a oval track close by. (150-175 feet in lenght) Could someone explain to me how differant wt. oil effects anything. Thanks for your time in helping me out.