This rubber hose connects the fuel tank to the fuel supply line, delivering diesel to the engine's injection system. It is a formed, flexible conduit that accommodates vibration and thermal expansion between the tank and the rigid chassis-mounted lines. The hose is constructed from a fuel-resistant rubber compound that resists swelling and cracking from diesel fuel exposure. A cracked or softened hose allows air ingress, causing fuel starvation and erratic engine operation. On replacement, ensure the hose is routed without kinks and that both end clamps are tightened to specification to prevent leakage.