i know bilstein makes the trd special for toyota , but ive heard that they are not the same as the bilstein HD, the rear HD are valved the same as the 5100 except the 5100 are used when the rear is raised up to 2in., the front HD are rated a little less than the 5100. dontt know rate of the TRD billies.
http://www.toyota-4runner.org/suspen...lve-rates.html