Ok, I value all of your opinions, here is my dilemma:

I recently purchased a '79 300D (188,000 miles) that has an immaculate interior, but does have some rust. Mainly the bottom of the doors so air/wind noise gets in. It also had some lousy paint work done along with some small amounts of bondo. This thing has been maintained very well over the years, however. I have records and a local indy adjusted the valves and checked things over and said the motor is in great condition. I had the injectors pulled and rebuilt, replaced the servo control (remanufactured), all filters, synthetic oil etc, etc. I love the car and enjoy the fact that I can do work on it - but do realize it needs some body work which will add up quickly. Ok, all that said here's my dilemma - I have the chance to buy a very clean, fully functional '83 300SD with 248,000 miles. Body is in better shape and has been maintained very well. What are the differences? I'm not familiar with the SD other than it sounds like they are more luxurious after reading through this site evry day for the past 3 weeks because now I am addicted to these darn cars! Which car is better? Does my '79 have a better motor? I know the '83 SD has a better tranny and climate control system. What are some differences that I should weigh before plunging into another purchase (besides how I'm going to explain this to the wife). Should I just be happy with my '79 300D and work on the body/paint as time and money permit? Knowing that it is at least very sound mechanically? Opinions welcome - Thank you.

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'85 300D - 206K (sold)
'81 240D - 149K (sold)
'03 Jetta TDI - (sold)
'79 300D - (sold)

I am considering having my 82 300D euro redone. It has a few rust bubbles, and could use a repaint. I got a quote of $2000 to fix all rust, clean up the body and give it a Glasurit base with clear in the original color.. the car runs so well, and it is so rare I almost want to do it.

We've discussed this topic many times in the past. You could search it. Basically, from a person who owned the 300D for five years, I can tell you that the 300D is very similar mechanically to the 300SD. The engine is similar, however, the 300SD is turbocharged and provides quite a bit more power (125 hp). This is especially noticeable, and appreciated, when driving on the highway. The SD is a bit larger and it might feel a bit ponderous around town.

You really need to drive the SD and see how you like it.

If you do not mind (or prefer) the larger size of the SD, then the condition of the body should rule the decision. Getting rid of heavy rust penetration is always a costly job. Depending on how it is done, the rust may return in the future.