I got a 1984 500sel euro and driving nicely or roughly i generally get 13mpg. When i first got it 12mpg was the best didn't matter if i ran 90 or 55. I climaxed 14.2 on the highway cruise set at 70 for an hour there and an hour back. Has approximately 200k on it. A hog but well worth it for the fun of watching a 6 grand shift. It has a 560 aircleaner now and a s600 grill. SWEET!