Can it be possible for two 4.0 6 cyl motors to have the same problem? Have 02 Sahara, had to have motor replaced with 90,000 on it. The motor that the shop allegedly put in has the same exact problem a year later. First and original motor had low oil pressure then the knocking started. I was told main bearings were bad. Had motor replaced, now having same exact problem a year later.
I'd say no, but because this is the newbie check-in area, you may not get the answers you are looking for. I suggest you check out this forum area and post your questions there, I think you'll get a better response.