Slide, Glide & ACE a Ride (on the Wild Side)
With This Penta Flat-6 Two Five
Since automotives is not really my thing, the flat-6 (b6) referred to here is none other than an old "5 cylinder" friend and Melodic Minor derivative, the Pentatonic b6.
As explained in several previous posts on the topic, The Penta b6 can be thought of either as a Maj. Pentatonic with a flatted 6th degree from the root (ie. C Pentatonic b6 = C-D-E-G-Ab), or; as being built from the 5th-6th-7th-9th-b3rd scale degrees of F Melodic Minor, in this case.
It can also be built simply from scale steps 1-2-3-5-b6 of the Harmonic Major Scale, but it's the Melodic Minor derivation that we'll be dealing with here.