I swapped in a 4-spd into my 85 300D, so I will say for the most part it is plug and play.

The 4-spd will bolt to the 5 cyl engine, use the FW from the 240 and have it matched to the auto FW plate. be sure to mark the plate and the crank so you then can bolt the manual FW to the same orientation. there should be a mark on the crank/FW.

use the 240D auto X mount for the trans mount. it has 4 bolts to mount it to the body.
The manual shifter will bolt into the same holes as the auto shifter.
The shift rods will have to be shortened and tweeked some to line up. not a big deal.
Use the front section of the 240 drive Line, and have it shortened and balanced along with the rear section at a good DL shop that can do the MB`s. good time to replace the U-joint and center bearing.
since you have both cars, then you will have all the parts except for the X mount. the 240 manual X mount is longer and only uses 2 holes and some have modifyied it. best to find a 240 auto mount.
The peddle assy will bolt right in, uses the same holes and 13mm nuts. the only difference between the two peddle assy, is, the manual with the clutch peddle has a longer shaft for the second peddle arm to hang on.

Your 240 will have the 3:69 diff, use the Diff from the 300D and it`s spedo. the spedo`s are matched to the Differential.

would be a good time to bolt on a new Master Cylinder while you have the peddle assy in your hands, instead of standing on your head working under the dash trying to bolt it on.

I picked up 3 mpg with the swap, and am pleased with it. I have the 2:88 Diff, and getting 30 to 31 plus on the Hwy. a 3:07 might be a better combination. it seem like with mine, there could be a gear between 2 & 3 and between 3 & 4.

Would I do it again? YES!!!

If some one has not done the swap and not interested in doing it, then you will hear all the reasons not to do it.

Will there be some expences to the job? yes. as with everything in life and worth doing, there is a cost.

have fun and take pictures.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works