Printing issue: consistent pattern to deformation in layers

[Roberts_Clif]

Looking at the Photo it appears to me to also be Z banding.
More information would be highly appreciated.

I solved my Z banding problem.
By applying a single wrap of electricians tape on lead-screw then inserted into the Coupler and connected coupler to the Stepper motor...

[ssv102]

curious aardvark and Roberts_clif,
Thank you for your quick replies. After your input I dug in more and after a series of tests found out it was Z-banding but was caused because the feeder gear was worn out and was not able to keep enough tension on the filament. After replacing it, everything started working nicely again.

Curious_aardvark,
Thank you for the insight on not being in my lab ;-) I will be much more conscience of providing better detail in any future posts.
My actual printer is a Geeetech Pro A (https://www.geeetech.com/wiki/index....pro_3D_Printer). However, there is very few original parts left on it after all my upgrades. I originally bought it real cheap and only bought it for the solid aluminum frame.
Again thanks for your help.