QUOTE(dstl1128 @ Jan 2 2015, 02:44 PM)
Motul H-TECH series on Group 3 or Group 4 base stock? Some say it is group 3.
Or which part in Motul website that mention its base stock type?
AFAIK motul did not disclose it's base stock.
most likely not group 3 as iinm European ruling forbids non group 4/5 to be labeled as full synthetic.
even if it is though it shouldn't matter if it is group 3 so long it meets api certifications/specifications along with other manufacturer specifications and of course it's own technical data sheet/specs.
personally, group 3 may even be better as group 5 ester have issues of swelling seals/softening them, while group 4 PAO have issues on shrinking seals.
group 3 did not specifically have any drawbacks other than being *supposedly* inferior than group 4/5.