Many hose suppliers recommend rubber hose for fuel because push-lock and other rubber hose ends are easier to put on and the hose costs less. We don't, and that goes for every brand of CPE-lined rubber hose, push-lock or braided, ours included: it is the nature of the material, not the maker.

CPE liners deteriorate over time with the solvents and ethanol in today's fuels. Some race fuels oxygenated with MTBE (methyl tertiary butyl ether), or carrying other additives, can make the liner swell and narrow the bore like a clogged artery, or turn it soft and jelly-like. Pieces can then break off and plug injector filter baskets, fuel filters and the filter sock on the fuel pump.

Rubber hose is also permeable: fuel vapour escapes through it, which is why you smell fuel around a parked vehicle, and standard rubber and CPE hose is not CARB compliant. That is a large part of why carmakers moved away from rubber fuel hose in the late 1990s and early 2000s. CARB-compliant low-permeation hoses do exist, but they use specialized liners such as FKM (Viton) and usually cost more per foot than PTFE.

PTFE is a different material altogether: it resists these fuels and additives and is essentially impermeable to fuel and most solvents. (We do not sell it as CARB certified: certification applies to a tested, finished hose assembly, and ours are assembled by the customer.) For fuel lines, use our conductive-lined PTFE hose with PTFE hose ends. Push-lock hose is a good choice for oil, coolant, vacuum, breather and boost lines.