Hello,
Thinking of getting a diesel.
What is the best year for 300D's. What model years had the
least amount of problems?

It depends. If you are looking at a 123 chasis, the '85 was the best for a number of reasons.

If you are looking for a 124, I'd buy gas.

As a general rule, the last model years of a model are always the best. This gives the manufacturer a few years to "iron out" the new model bugs. While this is true with most american cars, most notably GM (1980 X-body cars, Cadillac's V864 and Olds 5.7 diesel engines) all which after a few years became better. I dont think MB ever had this problem. The earlier 1970s 300D's are simplier regarding their climate control and vacuum systems but were less luxerious overall and therefore less desirable. The 1982-85 models were turbodiesels. More power, same economy.
A non-turbo charged 4-speed manual may save you some big repair bills in the future because of its relative simplicity compared to a turbo automatic, but the later models are definitely more livable and pleasing motorcars to drive.

The last year (1985) of the W123 300D was in fact the worst year. The 1985 300D was equipped with a trap oxidizer to meet higher emission standards. Essentially, the trap oxidizer would self destruct sending all kinds of junk through the turbo. Fortunately, you could get that evil contraption removed...

Oh yes, if you're looking for a W124 diesel, I'd recommend getting the 1987. These had the engine from the 300SDL and had AWESOME acceleration. (relatively speaking.) Later they used a 2.5 liter engine, and the car wasn't as "fast" anymore.

[Edited by speedy300Dturbo on 01-31-2001 at 02:15 AM]

Benzmac, I often toy with the idea of selling my 300SD and buying a W124 diesel. Why do you suggest the gas? Were the problems with the diesels?

Wasn't the trap oxidizer replaced free by Mercedes for anyone who had problems with it?

I don't know which model years had the least amount of problems, but from my experience, we had two 123's (82 and 83). The 82 was a European import with manual transmission. When I sold it, it has 240K miles on it. The 83 automatic which is still being used in my company is now pushing 350K miles and still going strong.

You have to get used to zilch power (even with the turbo kicking in), but they do run and run and run - you get the idea.

Ed

As for the 123 and 126 diesels with 617 engine, only the 1985 California model has the T.O. The Federal model does not have it making it the best of the years. Keep in mind that the 617 engine in the 1984/5 model has more power than the older diesels but it feels slower due to the smog control. The stock T.O. will go bad from time to time especially if the cars do not do much highway driving. MB would replace the T.O. with a new one for free in the past. The final recall replacing the T.O. with a catalyst should fix the problem. But the catalyst does clog up sometimes (very small chance but it happens) and you have to pay for it if the installation is over 12 months.

The 5 cyl 617 engine in 85 or older cars is trouble free. The 6 cyl engine in the 87D is a good engine but it dose have its share of problems. I think the '90-93 300D with 2.5L (5 cyl) is better. Living in California, I do not have much chance to test drive a 2.5L 300D, only once, and I found that the performance is very close to the 87 300D. Looking at the numbers from the book, 87 300D is about 10 second from 0-60 vs. 12 second for the 2.5L 300D, 14-15 second for the 85 300D/SD Fuel mileage: 28-30 m/gal, 34-38 m/gal, and 24-28 m/gal, respectively. 2.5L makes less noise and burns less fuel.

As for passenger space, the 124 body (such as 87 300D) will be very tight for 3 adults in the back seat, but the 123 (such as 85 300D) and 126 (85 300SD) have okay shoulder room for 3 adults in the back. 126 has more leg room than 123 body.

As for comfort, I like the 126, then 124, then 123. For some reasons, the steering on the 124 feels better than the others. I tested three 126 diesels (83-84 300SD) with 16 inch tires (stock is 14 inch) and they all handled as well as the 124 with stock 15 inch tires,or maybe even better.

David

[Edited by be459 on 02-01-2001 at 01:08 AM]