Trannys,rear ends,rear springs and idler arms. You will be replacing them in the life of an astro van, We service a fleet of them and every one eats idler arms every 30,000 miles. Every one ate at least one tranny and most have done a rear end in. As Twinn29 said,they are under sprung and need one more leaf to be a work truck but thats cheap to do. Count on at least one fuel pump failure too and thats not cheap!