Greg,

Germans list the grade of the hill as a percentage of the ratio of rise over run. Thus a 10% grade is rising 1 meter in a run of 10 meters. Which is pretty steep in real life.

You inspired me to get out my owner's manual for the 300D I imported and sold. It was in German and I got the owner an English version.

Under the topic of "Steigvermoegen," which translates into "climbing capability" the cars are listed as having the following grade climbing capabilities:

200D:
1st gear: 34% with either manual transmission, 36% with the auto box but with a note saying you have to have a "grippy" surface to achieve this.

240D:
1st gear: 41% with either manual transmission, 42% with the auto box but with the same note about grippy surfaces.

300D (non-turbo):
1st gear in all transmissions is good for 41%, again with that grippy surface.

Top speed in first gear for each car is:

200D: 37 km/hr
240D: 39 km/hr
300D: 42 km/hr

These are all with the manual transmission. They all are limited to 5,300 rpm, and they all come standard with 175 SR-14 tires.

This would indicate a final drive ratio difference of 13.5% in the overdrive direction for the 200D in first gear, which, considering it has 32% less torque than a 300D, is a serious disadvantage for the little bugger. It would seem you need to be running near 2400 rpm (the torque peak for all these engines per the manual) for the 200D to make the grade.

But, that park garage was not a 30% plus grade ramp. It might have been around 10%, but I cannot imagine it was much more as if it ever got wet stopping from any speed would be impossible. So, I think there is something else out of whack with Don Atienza's car. The right rear end ratio will help a lot, but it seems there is something else amiss unless that ramp was really steep. In that case it might not be practical to hit it at 15 mph in first gear, especially with some skinny or not folks in it.

By the way the grade capability figures were with 2 people in the car. Another couple of skinny people might actually make a difference of a few degrees, but I am sure the ramp was not a 34% grade.

Well, hope that helps a little, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)