250,000 miles on my '98 LS 400. Has only had reg. gas since 80k. 27 mpg on hwy. Maint performed at factory intervals. Timing belt, tranny, coolant, etc. Valvoline synthetic every 7500 miles ( I only drive on highways). Only now needs first non-scheduled fix: Rear upper control arm. The bushing is squeaking.
Great car.
Jeff