In my nearly 10 years of Mercedes dieseling, I've always dreamed about having a manual transmission backed 617 turbodiesel. Mercedes never made a manual 300SD, or brought any manual transmission 5 cylinder diesel cars to the US, so finding one stateside is like finding Sasquatch.
You can swap transmissions from the relatively common 240D 4 cylinder, but I've heard horror stories about drive-line vibrations due to the flywheel not balancing well to the larger motor. I never went through with a swap project because I didn't want to ruin a perfectly good car due to poor execution or missing parts, but the ghost of Rudolph Diesel must have smiled upon me last week when this car was listed for sale.
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It's a complete US spec 300D with a EURO-market 5 cylinder 300D manual transmission setup successfully swapped over, and several years of happy gear rowing under its belt. It was the perfect candidate to cannibalize for my 1984 300SD, a turn key setup I could reverse engineer to my larger chassis car with only a few modifications.
Now you might be thinking this poor little China Blue W123 is too damn nice to rip out its hope diamond and swap into my 1984 300SD. Based on the description I was even reluctant, but you have to remember one fact. All sellers of old Euro cars are liars. They either lie by omission, ignorance, or downright deception. In this case it was all three.
The car was described as having no rust. In reality this car has terminal rust in several obvious areas including the door bottoms, lower fenders, and along the back window. In addition to the damage disclosed on the driver's side, the hood was rippled like a couple of chubby teenagers were laying on it while trying to make second base.
Mechanically it was a basket case as well. The turbo didn't spool up, battery was not charging, window regulators dead, climate control totally F*#&$, and the list goes on except for the part that mattered to me. The transmission shifted fantastically. Even in the battered car it felt amazing. The executives at Mercedes were idiots thinking more manual transmissions didn't belong in the US. So with zero qualms about murdering the donor car, work was started today on the swap.
First let me introduce you to my 300SD receiving the swap. I purchased it nearly 2 years ago from a dealer friend of mine who found it at a wholesale auction in Dallas. It was traded in by the original owners for a Mini-Cooper. In the trunk was complete documentation spanning 30 years, from purchase details to every last oil change and repair. It is in fantastic original condition inside and out and by far the nicest Mercedes diesel I have ever owned. There's a thread documenting the last few years here. Here's a photo from Cars and Coffee last week next to my S600.
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Today my mechanic assessed the project and tore out all the components needed from the 300D. It's missing the nose and some other bits for another project.
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He also got started on the 300SD, removing the brake pedal assembly and adapting the mount for the manual pedals.
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The only part I've ordered so far is a speedometer from a 1989 300E. I needed a cable driven speedo that can be adapted to fit in the all electronic 300SD cluster. The 1986-89 300E have the same size speedometer face and share a similar rear differential ratio so the speedo reads accurately. Once everything is put in, the driveshaft can be measured and modified to the right length by a local shop.
My Mercedes diesel wet dream is coming true.
You can swap transmissions from the relatively common 240D 4 cylinder, but I've heard horror stories about drive-line vibrations due to the flywheel not balancing well to the larger motor. I never went through with a swap project because I didn't want to ruin a perfectly good car due to poor execution or missing parts, but the ghost of Rudolph Diesel must have smiled upon me last week when this car was listed for sale.
It's a complete US spec 300D with a EURO-market 5 cylinder 300D manual transmission setup successfully swapped over, and several years of happy gear rowing under its belt. It was the perfect candidate to cannibalize for my 1984 300SD, a turn key setup I could reverse engineer to my larger chassis car with only a few modifications.
Now you might be thinking this poor little China Blue W123 is too damn nice to rip out its hope diamond and swap into my 1984 300SD. Based on the description I was even reluctant, but you have to remember one fact. All sellers of old Euro cars are liars. They either lie by omission, ignorance, or downright deception. In this case it was all three.
The car was described as having no rust. In reality this car has terminal rust in several obvious areas including the door bottoms, lower fenders, and along the back window. In addition to the damage disclosed on the driver's side, the hood was rippled like a couple of chubby teenagers were laying on it while trying to make second base.
Mechanically it was a basket case as well. The turbo didn't spool up, battery was not charging, window regulators dead, climate control totally F*#&$, and the list goes on except for the part that mattered to me. The transmission shifted fantastically. Even in the battered car it felt amazing. The executives at Mercedes were idiots thinking more manual transmissions didn't belong in the US. So with zero qualms about murdering the donor car, work was started today on the swap.
First let me introduce you to my 300SD receiving the swap. I purchased it nearly 2 years ago from a dealer friend of mine who found it at a wholesale auction in Dallas. It was traded in by the original owners for a Mini-Cooper. In the trunk was complete documentation spanning 30 years, from purchase details to every last oil change and repair. It is in fantastic original condition inside and out and by far the nicest Mercedes diesel I have ever owned. There's a thread documenting the last few years here. Here's a photo from Cars and Coffee last week next to my S600.
Today my mechanic assessed the project and tore out all the components needed from the 300D. It's missing the nose and some other bits for another project.
He also got started on the 300SD, removing the brake pedal assembly and adapting the mount for the manual pedals.
The only part I've ordered so far is a speedometer from a 1989 300E. I needed a cable driven speedo that can be adapted to fit in the all electronic 300SD cluster. The 1986-89 300E have the same size speedometer face and share a similar rear differential ratio so the speedo reads accurately. Once everything is put in, the driveshaft can be measured and modified to the right length by a local shop.
My Mercedes diesel wet dream is coming true.
