The D4D engine as any common rail diesel engine is very sensitive to the quality of the fuel used. However I think the D4D on the SL market Hilux/Prado are not Euro 4, and are made to tolerate less quality diesel than Euro 4. Otherwise that engine will not be shipped to regions like South Africa and Australia. Also there is a 2ltr D4D variant that can be found on the UK Rav4 and Corolla which is not available on other markets. This I think that is a Euro 4 diesel.
By practice I have found super diesel to be better than normal diesel. D*MO and Prestige both recommend only super diesel on their Common rail diesel engines on the Mercs and Beemers. There are more examples of issues where the owner had used normal diesel over super diesel.
Sometimes agents say that normal diesel can be used at the point of the sale of a new vehicle. But then reccommend super diesel. This is a marketing gimmick.
And with my personal experiences with common rail diesels for over 2 years, I would advice anyone to use super diesel. That applies to Toyata D4D Hilux/ Prado, Mitsubishi DiD L200/Montero, Ssangyong Xdi Rexton/Kyron/Actyon, Kia- Hyundai CRDi Sportage/Tucson/Santafe/Sorento, Merc CDi, VW TDi, BMW Common rails etc....