I'm the proud owner of a 2003 D2 TD5 ES, with a month of trouble free fun - thank you for all the advice I gleaned from here before taking the plunge!

But I know the honeymoon will soon end, so some advice on what I need in my garage to carry out repairs would be much appreciated. I have a pretty good toolkit (no torque wrench), but what else should I have at the ready?

At the very least get a torque wrench; even putting the wheels back on requires the nuts to be torqued up to 140 Nm = 103.2 lbf
A good set of axle stands and a trolley jack (bearing in mind the weight of the vehicle!) wouldn't go amiss either even though you can probably crawl under the truck on your back without jacking it up. Oh, and a grease gun - the propshafts & U/Js have several grease points. And a multimeter should you wish to try and chase electrical faults.

Actually there's probably a whole host of stuff which people will come up with!

Diff.

Diff - much appreciated thanks. Any other suggestions welcomed.

Welcome