I have two very good running Mercedes. My 85 W123 with 617 Turbo has excellent compression and a very nice shifting automatic. I have had this car 4 years and engine runs 5 40 Mobil 1. But diesel is expensive, still at about $3.80 a gallon in central Indiana. Then this spring a I bought a very nice 86 W124, but it needed major head work. One rocker assembly broke loose and did a lot of damage. But I purchased an excellent M103 from John Heff and it is a delight to drive. I am running it on Mobil 1 also. This car is equipped with a 5 speed manual transmission. So I am doing some close monitoring of fuel costs on the difference between these cars. I commute almost exactly 50 miles on my two round trips to school each day to pick up my school bus. So fuel costs do mount up. I have been running 91 octane. My run is pretty open suburban and I drive an extra mile to stay out in the country. Typical speeds of 45 to 65 mph. What car do you think will cost the least to operate? I will give you the test results in a couple of days.

__________________
Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!

Maybe this can help you out, as far as fuel price and mpg comparison goes.

http://widgets.mslideas.com/dieselcalculator/

__________________
It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

I have 260K miles on my 190E 2.3 8v, so not only the diesels makes high milage.

Hmmm...... tough one. A diesel with a 3 speed auto versus a six with a 5 speed manual. I'd say its going to be pretty close but I'll vote diesel.

Nice fall weather the past few weeks gave us many sunny days with highs at around 75. I have driven and checked both cars on my 50 mile commute a number of times. The automatic in the diesel is a four speed of course. It does seem like a very unareodynamic brick and the best I can get is a pretty consistent 23.5 to just under 24 mpg if I really watch the tack and keep it under 2000. The 300E with M103 and a five speed stick seems to roll so much easier and the tests are all between 24.5 and 25 mpg. Tires are 15" with 165 sides with the 300D having the old 14" with a much higher sidewall. I kind of think that is responsible for the difference in rolling resistance. I do have to treat the 300E with a lot of respect to get that mileage as I do have a number of stop lights on my 12.5 mile run, which I run 4 times a day. I think there are six either stop lights or stop signs. If I want to rush the 300E it will quickly drop to 20 mpg, and a little abuse will quickly go lower then that.

__________________
Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!