E lawe i ke kalaka ma ke ʻano he laʻana, inā ua hōʻino ʻia ke sila ʻaila axle, e liki ana ka ʻaila mai ke sila ʻaila, a e hoʻopili ʻia ka ʻaila i liki ʻia ma ke kūlana o ka paleki. ʻO ka pōʻino pololei loa o ka ʻaila ma ka paleki, ʻo ia ka hāʻule ʻana o ka paleki. Inā he mau pilikia i ka wā e hoʻokele ana, ʻoi aku ka weliweli o ke hehi ʻana ma luna o ka paleki. Eia kekahi, e nele ka ʻaila i ka pūʻolo hope, a aia nā huila nui a liʻiliʻi a me nā huila planetary [i kapa ʻia ʻo differential] i loko o ka pūʻolo hope, I ka hihia o ka nele o ka lubrication ʻaila kia, he mea maʻalahi loa ke hōʻino i ke kia i loko o ka pūʻolo hope.