Tim.. said:
Personnally, as long as you dont drive it very hard 100% or tow heavy loads
in high ambient temps, and use a good spec mineral oil of the correct
viscosity, changed at around 5k intervals, then I would NOT switch to
Synthetic.
I always wonder why oil changes are done so frequently in the US, even
on European cars. I'm driving currently a new V70 D5 (185 hp) and
before I had a V70 T5 (260hp). In Europe oil changes are done every
20'000 to 30'000 km (13'000 to 20'000 miles) or after 24 months which
ever comes first. But along with the engine oil the filter is always
changed. Shorter intervals are only recommended in very sandy or dusty
environments.
The other thing is the frequent statement in this NG that the switch
from regular mineral based engine oil to fully synthetic engine oil on
high mileage cars is producing oil leakage. If that were the case the
engine has *IMHO* a major structural defect. Molecule chains of fully
synthetic oils remain much more stable which results "thicker" oil when
hot. From the standpoint of physical properties of the oil qualities
there is no reason not to switch to synthetic oil.
Joerg