The rear end ratios are different, as is the tranny gearing.Why is the EPA for the C320 higher than the EPA for the C240 (e.g. 20/26 Automatic vs. 19/25)? The 320 is over 100 pounds heavier and puts out 47 HP more than the 240. Does this hold true in real driving? If so is it the gearing?
The EPA obtains their figures from lab tests and the car on a dyno (for objective comparison reasons). Therefore you do have to take them with a pinch of salt since lab tests do not always reflect real world tests .Thanks Drew. I have a 2003 C240 4matic. I decided the extra cost of the C320 was not worth it to me for the extra power (although, I traded in an Audi S4), even though the EPA was about the same. I just wondered about the EPA estimates, as it seemed strange. Longevity is not an issue as I won't keep the car more than 4 years. Thanks again.