  We present measurements of both scale- and time-dependent deviations from the
standard gravitational field equations. These late-time modifications are
introduced separately for relativistic and non-relativistic particles, by way
of the parameters $G_{\rm matter}(k,z)$ and $G_{\rm light}(k,z)$ using two bins
in both scale and time, with transition wavenumber $0.01$ Mpc$^{-1}$ and
redshift 1. We emphasize the use of two dynamical probes to constrain this set
of parameters, galaxy power spectrum multipoles and the direct peculiar
velocity power spectrum, which probe fluctuations on different scales. The
multipole measurements are derived from the WiggleZ and BOSS Data Release 11
CMASS galaxy redshift surveys and the velocity power spectrum is measured from
the velocity sub-sample of the 6-degree Field Galaxy Survey. We combine with
additional cosmological probes including baryon acoustic oscillations, Type Ia
SNe, the cosmic microwave background (CMB), lensing of the CMB, and the
temperature--galaxy cross-correlation. Using a Markov Chain Monte Carlo
likelihood analysis, we find the inferred best-fit parameter values of $G_{\rm
matter}(k,z)$ and $G_{\rm light}(k,z)$ to be consistent with the standard model
at the $95\%$ confidence level. Furthermore, accounting for the
Alcock-Paczynski effect, we perform joint fits for the expansion history and
growth index gamma; we measure $\gamma = 0.665 \pm 0.0669$ ($68\%$ C.L) for a
fixed expansion history, and $\gamma = 0.73^{+0.08}_{-0.10}$ ($68\%$ C.L) when
the expansion history is allowed to deviate from $\Lambda$CDM. With a fixed
expansion history the inferred value is consistent with GR at the $95\%$ C.L;
alternatively, a $2\sigma$ tension is observed when the expansion history is
not fixed, this tension is worsened by the combination of growth and SNe data.
