If you do a search or look through my older posts you will find lots of info with regards to the flange/axle wear.
I also have two videos here which show the wear:
https://www.youtube.com/channel/UC0g...Uwpq2Qivaj_wbg
re oil lubed: Ive found removing the axle seal and allowing the splines to be lubed with oil from the diff is simply not enough. Ive had a few Defender TDCi models in now that had been upgraded to the HTE (brand name) axles and drive flanges, with the axle seal removed (as in the axles were well wet with oil from the diff) and the splines had still flogged out.
*Regular greasing of the splines works, say every 20K, which is easy done once the HTE or Ashcrofts (brand names) axles/drive flanges are fitted.
*The front as its not prone to the same amount of torque loading only requires the flange to be upgraded.
*The shims are only on the front axle/drive flange.
*The red rust dust is the fretted material that has oxidised.
Regards
Daz