Has anyone experienced any problems w/ the engines in their 2nd Gen xBs? I found some info from a Toyota Tech:
andhave replaced 2 08 xb complete engines in the last 2 months with the same problem with less then 5k on both, it is a problem with the counter balancer assy. the bearing material is failing and seizing to the counter balancer shafts most likely due to toyota getting the bearings made form a diffrent supplier then the previous 2az-fe the reason their sending complete engines is because their getting them straight from japan with the old manufactured bearings. also i have never had a internal engine issue with the 2az-fe in the camry i dont know if only the xb was getting the new bearings or what. at the present time their are no tsb's or recalls (i actually checked yesterday) but i wouldnt be suprised if their is one shortly
from what i have seen and what the toyta rep has told us about this problem is that the bearing themselfs are not true, a manufacture defect where one side of the the bearing has a closer tolerence and the outher to great, witch can cause poor lubrication so its kind of both form what i understand. the bearing seize to the bal shafts then spin in their journals eventually falling out into the solid jounal struture that kind of has a little pocket pocket in the bottom of it. this just destroys the upper and lower journal , but the upper is part of the no.2 oil pan so basiclly the whole bottom end of the engine case would have to be replaced plus the balancer assy then u have the issue of (on the last on i did) huge metal flakes through out the entire engine and potentially have caused or will cause outher failuers later. also the bal shafts are matched to the bearings and the case due to variences in the block so replcement of the shafts are very time consuming and difficult. and i belive possibly that manufacter of those bearings also produced all the bearings in the engine but for some reason the bal shaft bearing are more prone to the failure then outhers i think thats y toyota are sending complete engines from japan.