I'm guessing that the default type of residuals may differ between GLIMMIX and MIXED.   The GLIMMIX documentation (for the plot option on the GLIMMIX statement) says: ALL requests that all plots appropriate for the analysis be produced. In models with G-side random effects, residual plots are based on conditional residuals (by using the BLUPs of random effects) on the linear (linked) scale. Plots of least squares means differences are produced for LSMEANS statements without options that would contradict such a display.   The MIXED documentation (for the plot option on the MIXED statement) just says: ALL requests that all plots appropriate for the particular analysis be produced.   I suggest that you explicitly specify the type of residual for the plots that you want. If that doesn't sort it out for you, I suggest that you ask tech support.   I hope this helps.       ... View more