which Year model you have ?
Between 1980 to 1992 BJ 60 had 3 variants of diesel motors coupled to 1 Auto transmission & 2 type manual transmissions
if you have a vehicle in stock setup, read the id plate and share data. There exist at least 4 Toyota diesel engines of different pedigree which can be coupled to STOCK drive train of BJ 60 without any change. (drive train = transmission, transfer case & differentials)