We present a three epoch survey for transient and variables in the extended Chandra Deep Field South at 5.5 GHz with the Australia Telescope Compact Array .
A region covering \sim 0.3 deg ^ { 2 } was observed on timescales of 2.5 months and 2.5 years and typical sensitivities 12.1 - 17.1 \mu Jy beam ^ { -1 } ( 1 \sigma ) were achieved .
This survey represents the deepest search for transient and variable radio sources at 5.5 GHz .
In total 124 sources were detected above the 5.5 \sigma level .
One highly variable radio source was found with \Delta S > 50 \% implying a surface density of \sim 3 deg ^ { -2 } .
A further three radio sources were found with lower levels of variability equating to a surface density of \sim 13 deg ^ { -2 } above a detection threshold of 82.3 \mu Jy .
All of the variable sources have inverted radio spectra ( between 1.4 and 5.5 GHz ) and are associated with active galactic nuclei .
We conclude that these variables are young gigahertz peaked-spectrum sources with active and self-absorbed radio jets .
We explore the variability completeness of this sample and conclude that the fairly low levels of variability would only be detectable in 3 - 25 % of all sources within the field .
No radio transients were detected in this survey and we place an upper limit on the surface density of transient events < 7.5 deg ^ { -2 } above a detection threshold of 68.8 \mu Jy .