heres a pic of both drums, obviously the bigger drum is the "areostar" drum
i did have 10" drums stock, and all in all i dont know that you would notice a difference going from 10" stock drums to the areostar spec drums in normal driving. i did tighten up my adjusters some when i put my new drums on, so i do have a better pedal now, but that would be the case with any drum setup be it 9", 10" stock or upgraded. the benefit is when your stopping the larger drums will take more heat and not develop brake fade as soon and there is alot less chance of drum warpage or cracking. the fins around the drum also help it cool back down when your rolling again. sure, a disc brake setup would be a better upgrade and give more noticeable improvement as far as stopping, but im not about to bother with all that on a 16+ y/o truck. the areostar drum upgrade will do for me. i'll know more once i take the trailer somewhere, lately its just been back and forth to work, 4 miles each way with only a mile and a half outside of town at highway speeds. one odd thing, when i first got my truck and i needed to do rear brake service, i had to bust the drums to get them off, they were rust-seized to the axle flange. those drums did have some fins around them similar to what the areostar drums have. thay werent the same drums i have now, but they were better than what i replaced them with. im not sure if there are 2 different specs of areostar drums or if certian rangers may have came with finned drums factory. (mine is a 5040 gvwr) i always use a bit of anti-seize between the drum and where it mates to the axle flange now. i dont think i could bust these new ones apart. the autozone part # for the areostar drum i got is 8994. i asked for "areostar drums, '93 2wd 4.0" and yes, they did just slide right on, ive heard that the newer axles like the 31 spline in the fx/4 wont work due to the hub being a bit larger where the inner flange slips over, but on the older 28 spline 8.8 with the stock 10" drum is a direct fit.