I could be wrong but no movement is ideal. If you have more than a little...Like you said, contact BNR...
Oh BAC5.2 is pretty good twith this type of thing too...
204,000miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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