It's big odd at first to get used to the new gearing, tend to use 3rd more in town and linger in 4th as main gear unless on an open fast road. 5th doesn't like motorway hills anymore. More smoother quieter drive on motorways, cruise speed increases to a comfortable 70mph, I wouldn't go back to the old ratio on my 300tdi 110 now. But do not think a disco ratio box on a 300tdi defender works as well as it does on a TD5 defender where that engine has power to overcome the short comings of leggy gears.
I put a tranny from an early TD5 D2 on mine. Just had to swap the rear output housing to give it a speedo drive and the output dog to allow pto drive for my winch. Went for that box because it was low mileage, quieter as the disco 200tdi boxes I came across were high mileage noisy worn boxes.
