GL4 80w-90 gear oil for diffs and Trans box and TFQ auto transmission fluid if u have a R380 gearbox.
http://www.castrol.com/castrol/iframe.do?categoryId=9024084&contentId=7044829
not quite sure what the TFQ is, is that from another brand?
If he's going to Halfords he'll probably buy Castrol or Mobil, Mobil is the better of these two
Castrol Syntrax Universal for the diffs and transfer box
Castrol TQ-D for the gearbox
Castrol Magnatec Diesel 10W-40/Edge Turbo Diesel 0W-30 for the engine
Mobil list Mobilube 1 SHC 75W-90 or Mobilube GX 80W-90 for the tranny and diffs
Mobil 1 synthetic ATF/Mobil ATF 320/Mobil ATF 220 for the gearbox
Mobil Super S 10W-40 for the engine
If you're going to buy engine oil from Halfords i'd buy Mobil Super S 10W-40 rather than the magnetec
You could try your local Shell garage as their oil is better quality and spec than Castrol with Mobil being about equal (apart from their semi synth engine oil, Shell is slightly better) and maybe competitively priced with the prices at Halfords
Shell list
Donax TA for the gearbox
Helix Plus 10W-40 for the engine
Spirax GX 80W-90 for the diffs and transfer box
i would use the Shell over the others as you get more bang for your buck generally
no one recommends standard EP 80W-90 for it anymore as far as i can see