thanks maxwedge. yes a 3.1 i checked position of lifter seat and it was all the way up even when opening valve. i removed one set (intake and exhaust on one cylinder). i could not compress them at all. i decided to take these 2 apart. they were stuck tight, when i got them apart and cleaned and lubed and reasssembled, i could compress easily. after re-installing these i now have 140 on compression gage. i will now take them all out and check. why were they froze is a confusing me now. if their tolerance was too close they may freeze up again. one mechanic said they were possibly put in dry as he always soaks them overight first. this is my mother in laws car and i was told it was clicking or knocking and the dealership talked her into replacing lifters.thanks dadio, i did go to advance auto and compare lenghts and they were the same. the correct lifters must have been installed. i now worry if by freeing them up my problem is solved or if i should make the dealership buy her new ones. thanks for the help i will post the results.