i ran schaeffers 15w40 in my truck, and about 200 miles before i was to change my oil, i put a bottle of x1r in as directed from them. now since schaeffers already has an excellent barrier lubricant in the oil, i never noticed any difference when i put the x1r in. after 200 miles of normal use, i drained and pulled the sample. when the lab results came back my concerns were a reality.
with 6600 miles on my oil the results showed my ep/antiwear (zinc/ph) levels higher than norm for this amount of miles (zinc-1180/ph-1078 norm would be around 730-850). also the detergents (cal) was much higher at over 3660ppms (norm 730-850ppm). now what that did is elevate my oxidation level that was norm was at 33.
i also found sulfur levels that was never a problem (always at 0 out of 100%) now at 30%. my viscosity level was higher than normal, (15cst) where as it would be around 13.47-14.
my thought on this is, i will personally never run x1r in anything i own again. i can see where in a race application, this is an excellent way to add some extra protection but, then the oil is changed after a few races and race engines are subject to rebuilds more often than personal car engines so the oxidation doesn't have time to do any damage to the soft metals. with higher levels of oxidation, your soft metals would begin to show possible damage by using this technology in a conventional engine.
This barrier additive does work as such but it inbalances the additives not allowing the oil to do its' job.