  After about 18 years of steadily spinning down, the accretion-powered pulsar
4U 1626-67, experienced a torque reversal at the beginning of 2008. For the
present study we have used all available Fermi/GBM data since its launch in
2008 June 11 and over 5 yr of hard X-ray Swift/BAT observations (starting from
2004 October up to the present time). This second detected torque reversal is
centered near MJD 54500 (2008 Feb 4) and it lasts approximately 150 days. From
2004 up to the end of 2007 4U 1626-67 the spin-down rate decreased at a mean
rate of ~ -5.5E-13 Hz s-1 until the source reversed torque again. Since then it
has been following a steady spin-up at a mean rate of ~ 5E-13 Hz s-1. In
addition, 4U 1626-67 increased its flux simultaneously (a ~2.5 factor). We
present detailed long-term timing analysis of this source and a long term
spectral hardness ratio study in order to see whether there are spectral
changes around this new observed torque reversal.
