Don't know for sure but I suspect 4-wheel drive might have something to do
with it. On my 4WD '92 Ford F150 with a 5.8L V8 the oil capacity is 6
quarts. And my 72 Bronco with a 302 V8 had 7 quart capacity as I recall. I
imagine that it is because of the weird angles that the vehicle is expected
to operate at vs the oil sump design.
Or not......<grin>
GQ '67 Safari
4082 in CA