f1justin

i was 4xing about a year ago threw it in 4 low on my 04 f1. as i made my climb up a hill something snapped and 4x4 was no more so on that note i drove for about a year 2 wheel no problem. i recently just baught a new trans case from a junkyard $450, slapped it in and i was getting a bad vibration. so i took off my front drive shaft and it eliminated the proplem, i had it balanced and tried again still had vibration, so my next step i took t case back to junk yard and had them go through it. and it still makes vibration. im at my witts end and pretty fed up. the yard doesnt want to blame problem on t case but im pretty convinced. has anyone had any kind of t case issue on thier trucks?