Which of these two models will be the least expensive and least complicated to own? How much worse will fuel economy be with the 300SD vs what I got with my trustworthy old 300D?

I will keep both the "old" 1983 300D w/272,000 miles, and the "new" 1983 300SD with 99,500 miles on it. Then, when I get tired of paying for an extra storage spot, I will have to sell one of them.
Which one will it be? Hmmm... The D has been such a good reliable car, while the SD has low miles (for a diesel) however presently has a dent in the drivers door that I must have repaired.

I am just hoping to get advance information from anyone who has owned both.

In general....
I believe that the W123, being a bit simpler is less expensive to maintain. There are also many more 123s in the junk, I mean recycling yards so the availiability of used parts is higher.
However, in your specific case, the lower miles on the SD may make it the less expensive to keep. What a coice! Wish I were in your shoes on this one.

Easily the 123 is easier and cheaper to keep for the reasons mentioned already. Why don't you pull the engine from the SD and keep it for when you need a new one in the 123 ?

My preference is the 300D because I like the exterior "size" better. The SD gets better fuel mileage because it has some aerodynamics designed in. I take the SD whenever I have to cover alot of interstate miles though.

__________________
Jim

I have owned both. I prefer the SD. The D may be a little simpler to work on but the comfort level and the power make the SD the obvious choice.

__________________
'85 300SD (formerly california emissions)
'08 Chevy Tahoe
'93 Ducati 900 SS
'79 Kawasaki KZ 650
'86 Kawasaki KX 250
'88 Kawasaki KDX200
'71 Hodaka Ace 100
'72 Triumph T100R

Both cars have the OM617. The lower mileage SD smokes like crazy, while my trusty and well-used old 123 doesn't smoke at all, and can move with the fast guys on the open highway. Both have rather well worn interiors, with the SD being blue leather, and the 123 being tan MB-Tex.
Actually, the leather looks worse, and the SD needs a new dash pad. The MB-Tex looks a lot better, really.

I expect to sell my D for the same amount that I will have to borrow to buy the SD. But the D is easy to parallel park, while the SD is a whale.
I am very suprised to hear that the larger SD gets better mileage.

Both engines sound exactly the same. The SD transmission shifts far smoother, and the SD rides a lot better. The turning radius of the 123 is amazingly tight, though - far more nimble than the SD.

The D hasnt got a speck of rust, while the SD has recent paint, so I dont know what is underneath the new shine. The former owner (who was the second owner) is dead, so I cannot find out very much about the maintenance history.

...but a 1983 OM617 with 99,500 verifiable miles on it, (compared to the 272,000 on the D) according to Carfax....Hmmm. Quite the dilema. What to do...?
I have 2 more days to make a decision.

I've never gotten the straight answer on this - for the same year model, 81 through 85, what about an SD is more complex than a 300D?

I'll list the differences I'm aware of:

- SD guide rod mounts have 4 extra bushings.

- some SDs have ABS, I haven't heard of anyone having problems.

- some SDs have airbags, I haven't heard of anyone having problems.

- SD central locking has its own electric pump, doesn't take the shut-off valve and ACC down when central locking fails, actuators and vac line scheme are simpler.

- SD cooling system takes couple more quarts of coolant.

Okay, power seats can and do cause problems. Is that what all the worry is about? From what I've read on this forum, 123 oil cooler hoses are more problematic than 126 oil cooler hoses. That worries me more than seats that won't move.

Lots of valid reasons to choose one over the other but I don't see how compexity or cost to maintain and repair are worth a second thought. I mean Ducati has a valid decision to make over a seemingly better car and lesser car. None of the points of comparison mentioned have to do with complexity or cost to maintain and repair.

Or is it just late and I'm being cranky?

Sixto
95 S420
87 300SDL

No, you dont seem cranky at all. Maybe you are just getting fed up with explaining these differences to ignoramus' like me.

Cost of maintenance is important to me. And as I have to do all of my own maintenance outside in the open, rather than in the nice cozy well lit garage that I used to have, ease of maintenance is a big consideration, too.

But Man, that SD is sure a great looking car, and rides so much nicer. Am I being influenced by the same Bigger Is Better mentality that seized my father back in 1971 when he traded his gorgeous Olds 442 in on a Cadillac? I never forgave him for that.

The main attraction to the deal is the utility of having an OM617 that is only just broken in, by diesel standards.

as you describe the 123 over the 126 I seem to read into it that you prefer the D because of its nimbleness and size. This is important to consider because it is not fun to drive a car that you don't like.
Although the SD maybe more favorable to you in some areas, will you enjoying your drives in it?? That is a question only you can answer.

Personlly, I have both. I do not like driving the SD because it feels like an ark to me...It is mostly my wife's transportation. She likes it over the 123...That is perfect for me. I only drive it when I fill it up or do maintenance on it. Even at that its too often for me..

__________________

79 240D my current toy
42 years a Diesel addict

240D sold
250SE sold
220D sold
280C sold
280S sold
300D (2) sold
300CD sold
300DT sold
300SD sold
380SL sold

W126's are complicated if you are used to Model T fords and 50's Chevy's. They are extremly simple cars to fix and maintain. Actually their is probably more room under the hood on a W126 so their is more access. W126's are about as simple as it gets.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I have not owned a D.

I had an SD, killed it 2 years ago in a chain crash.

Presently driving an SDL, which gets better fuel mileage than the SD.

Don't factor in the fuel cost, since the difference will probably be minor compared to the other factors involved in maintenance.

Maintenance, and "grin factor" will probably wind up offsetting, resulting in a tie...

Sounds like you can't lose either way, so relax and follow the star on the hood.


Best Regards,
Jim

Aw Hell - I am going to keep both cars. I will park the 123 & drive the 126 for a few months. (Too bad parking is so expensive). Then, when I decide, I will get the "loser" detailed and sell it.

I have owned 4 W123's and 1 126. 300SDL

Order for cost of owning.

W123 240D
W123 300D non turbo
W123 300D turbo
W123 300TD non turbo
W123 300TD turbo
W123 300CD non turbo
W123 300CD turbo
W126 300SD turbo
W126 300SDL
W126 350SDL

I place them in this order ONLY due to the amount of bells and whistles to maintain and repair.

NOW the most complicated factor in ownership cost, is that all these cars are 13-24 years old. So which one is the cheapest to own that depends on how it was maintained. I owned 2 1982 300TDs at the same time. The one I sold after 2 years always required work. The other one I have owned for 14 years and it has been the cheapest car I have ever owned.

Now for the comfort equation. SDL then SD then 300 turbo then the non turbo then the 240.
The 240D will be by far the cheapest to own and operate IF they are both the same level of maintainence.

Your comparison of the 2 you have. 300D simple, utilitarian, reliable. The SD much more luxurious, but more bells and whistles to maintain.

I think you have a good plan. Operate them both for a while and see which one seems the better of the 2.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

I have a 300D W115 and a 240D W123. I have had in the past a 126. I also have a W201 190E 2.6. I like the 123 far and above all the rest. Although I have enjoyed all of them to some extent. The 123 just feels right. Y'know like a good comfortable pair of slippers.
I bought it for a song when the previous owner was told it needed an engine and transmission overhaul. It started OK, but had very little power, shifted hard and the fuel economy had taken a dump.
The body is straight and shiny. After cleaning the interior, It's beautiful inside. After changing the air and fuel filters, It has ran like a watch since.
I have been asked if I feel bad about taking advantage of the situation, the answer is a resounding no. The previous owner was a smoker who did everything on the cheap. So I feel like I rescued an old friend from certain demise.

__________________
83 W123 240D
76 300D, "Lil Yellow Car"
1978 Cessna 172N 180 HP Mod

"If life ain't fun, I'm not interested"

The important things are those that you learn after you know it all.
Chip Foose

Build a better mousetrap and you will REALLY infuriate corporate america.

It's late again so I must be cranky again

Dave, please name these bells and whistles for the SD besides power seats and rear seat reading lights. I don't profess to knowing much about 123s but the ones I've seen seem to have as many bells and only a couple fewer whistles.

Thanks,
Sixto
95 S420
87 300SDL