Not really, although I find the fuel gauges tend to drop rather fast when just below half a tank. I suggest that, as the cars age, oldest now eighteen years old, the rubber pips will slowly get porous, and cause fuel supply problems, like poor starting due to air bubbles forming in the fuel, and possible fuel seepage anywhere along the fuel lines. Coolant hoses and air boost pipes will also soften and fail at lower pressures than at new conditions. I have had Discovery TD5's with 21 gallon tanks, and filling an empty tank can be quite an investment. I remember a chap filling one and a bill of £130, which he could not pay, on Anglesey twenty years ago. I filled the tank on my TD5 petrol tow car three times that weekend!

Well glowplugs next.