I read in LRO that replacing the transfer box with one from a Discovery, or possibly a Range Rover, would give a higher cruising speed.
I’m interested in carrying out this swap on my own vehicle. What’s the best way to achieve a comfortable cruising speed of 60-70mph? Which option would give the quietest running conditions? How difficult is it to change these parts?
David Hanna, Chelmsford, Essex
It’s the Discovery 2 transfer box high-range gears that you need. These are Q-specification (ie, quiet-running) fitments that, incidentally, are already fitted to some Td5 Defenders.
Rather than shell out for a complete new transfer box, or risk a used one, the best option could be to contact Ashcroft Transmissions (ashcroft-transmissions.co.uk), which supplies the high-range Q-gears as a conversion kit.
This set gives a 15 per cent increase in gearing, reducing high-speed noise levels at the same time as leaving low-range gear ratios unaffected.
The uprated gearset can be fitted on a DIY basis after removing the transfer box. Alternatively, Ashcroft will fit the gears for you, or supply/install a reconditioned transfer box fitted with the high-ratio gears. We showed how to carry out this high-range conversion in the June 2010 issue.