5 models (XJ's and MJ's [have a sixth, but the rear end is now disc]), 2 different size of brake shoes. After looking at this mess, I noticed that it seems that 1) IF your brake drums have fins, then you have the longer, thinner shoes. 2) smooth drums equals wider shoes and 3) Jeep used whatever was on the rack at the time at the factory. The brakes (complete) WILL enter-change from axle to axle, e.g. D35 to Chrysler 81/4. Wheel cylinders seem to be the same, regardless of shoe size.