for maintenance ng brake balance sir. since ang sasakyan (ayon sa batas ni newton) ay magweweight transfer towards the front during braking, ang mangyayare e gagaan yung likod at maaring mag-lock ang rear brakes (can lead to "fishtail").
yung lspv is there to control the pressure towards the rear brakes with respect to the load. kapag mabigat ang load, it will provide more pressure to the rear brakes and vice versa kapag magaan (or no load).
ganito hitsura nun. connected to the suspension for load detection (sensing). yung iba kasi hindi load sensing. simpleng proportioning lang ang ginagawa.
borrowing my pic:
http://tsikot.com/forums/redirect-to...LSPV1.jpg.html
halos meron neto mga pickup truck at suvs.