W124 diesel sedan/wagon drivetrain interchangeability

[240dddd]

Hello,

If I have a 1987 w124 300td without a transmission and engine what are my potential donor cars (besides another w124 300TD)? Will the tranny and engine from a W124 300D sedan swap in nicely, or were there significant differences in the wagon drivetrain? What about an 86-87 300SDL?

[tjts1]

The 300d 300td and 300sdl from 1986-87 share the the same engine and transmission. Everything is interchangeable.

[vstech]

Originally Posted by tjts1

The 300d 300td and 300sdl from 1986-87 share the the same engine and transmission. Everything is interchangeable.

as far as I'm aware, the 124 uses a mechanical speedo, so the 126 transmission would not be a direct swap. you could pull the speedo and wiring from a 93/4/5 420E as they have an electronic speedo (as a matter of fact, I've got one in a yard near my house...)
the 90-93 300D uses a 722.418, a much lighter duty trans than the 87, and of course the motor is 5 cyl, not 6...

so, any 87 300D/TD would work for the trans, but the engine can come from any 86-88 SDL or a 300D/TD as the 603 3.0L is the same across the board. but the motor mounts are different, so keep them with the car.

[Mölyapina]

Originally Posted by vstech

motor mounts are different, so keep them with the car.

You mean engine mount arms (the metal arms that run between the engine and the body)?

[vstech]

Originally Posted by Jooseppi Luna

You mean engine mount arms (the metal arms that run between the engine and the body)?

yes. you will need 87 300D engine mount arms.

also, the drive shaft is the same length, but the yoke is smaller. if you get a 90-93 drivetrain, you will need to get the differential as well. you DO NOT want to swap yokes between diffs... preload is difficult to figure in the car.

[sixto]

The tandem power steering and SLS pump is unique to the wagon unless you find a very rare SDL with SLS. Don't pass up a good engine because it doesn't have a tandem pump, though. As a matter of fitment, the 603 from a 350SD/L or W140 SD/S350 is basically the same engine with known issues. The donor might have a 3.0 block so check serial numbers. With a bit of work you can swap in the 5 cylinder engine and 722.4 transmission from an '87 190D turbo or 90-93 300D 2.5 turbo to make a 250TD turbo. The 250TD was available outside North America. I don't know about a 250TD turbo. I'm pretty sure the same tandem pump will work. If you don't need to climb or merge in a hurry, you can try the 5 cylinder engine from an 86-89 190D 2.5. I don't know if the prop shaft from a W124 2.5 sedan is a drop in fit for a wagon. There might be a smaller yoke at the diff too. There's always the 2.2 liter engine from an 84-85 190D but I don't know if the tandem pump will attach. I think DieselPaul has a W124 200TD.

If you get a W126 engine, swap in the oil filter cover from a W124 or W140 *before* the engine goes in. I don't know which cover 190D engines come with.

Sixto
87 300D