Differences between 99 and 98 E300 D
 

Were there any differences between these two model years other than including leather as a standard feature?

Yea, the 99 has leather seat inserts full leather was an option, 98 could be had with leather or tex, the 99 had a digital data bus area network, all audio etc played thru, and the 99 had head protection curtians, other than that same car.

From what ive seen on autotrader it says that the 98 soes 0-60 in 8.0 second but the 99 does it in 9. the 99 is also said to get 2 mpg better on the highway. this seems to me like a lower axle ratio but i may be wrong. other than that and what was previously posted i dont know of any other differences.

Can someone confirm those 0-60 specs? Is there a good source for acceleration specs in other models, specifically the 124 chassis?

There is no difference in the drivetrain or performance

Don't forget, the spare wheel is no longer a full size alloy in '99. It is steel.