Manual transmission from a 240D to a 300TDT?

[ubertino]

I'd like to replace the automatic in my 1982 300TDT with a manual transmission. I've got a line on a 240D 4spd manual, with pedals, linkage, driveshaft half shaft, near as I can tell everything but the slave cylinder and flywheel bolts.

Will the 240D four speed swap in ok?

My points of concern are the mounting points and possible brackets, length of transmission in relation to length of driveshaft, and if my wagon is going to require a different drive shaft then the sedan. I'm also not certain that the transmission will bolt to my engine.

Any input from the wisdom of the crowd would be appreciated.

[vstech]

flywheel may require match balancing to your engine, it may not though. have it checked against your auto flywheel. it will also be underweight for a 5cyl, but it's close. the official ones are rare as hens teeth in the us...
all will bolt in, you will need to shorten your front shaft 4" and the shift linkage about the same.
also, you will need to aquire a transmission mount plate from an auto 240D. aside from that, it's bolt in.

[t walgamuth]

This is a pretty common swap as the 123s have aged. The automatics are very rugged but when they get old they tend to be finicky to keep operating properly.

There is a huge slug of information here if you search for it.

I have done at least three or four stick conversions. The tranny bolts right up. you need the flywheel, clutch assembly, the driveshaft will need lengthened or a different section swapped in. you will need a different tranny cross member, probably, and the shift arms will need shortened as the rear of the 300 engine sits further back in the chassis.

the trickiest part is the flywheel which usually is neutrally balanced but occasionally is balanced with the crank. you need to mark your existing fw and crank when you remove the fw from your existing motor then check it for neutral balance. if it is not neutral you will need to match balance the new fw so it will mate comfortably with your crank.

if cone correctly this is a hugely satisfying conversion. your fuel economy will increase at least 2 mpg.

good luck

[ubertino]

I did a search, with little success. Anybody help me out with some terms? Transmission swap is a bit too broad.

[Skippy]

Try manual conversion. Someone, possibly R Leo did a pretty extensive writeup on the procedure.

I gained about 2-3 mpg from my swap, and the car is much more enjoyable to drive now.

[charmalu]

I swaped in a 240 4-spd into my 85 300D, your TD is no different.
the manual trans mission will bolt right up to engine adaptor plate.

use the front section of the 240D drive line. It will have to be shortened about 4 in and rebalanced as a whole unit. (complete DL).

use the 240D automatic cross mount.

as i remember, there are 4 wires from the NSS (nutural safety switch) 2 are for the back up lights and the other 3 are for the start. as I remember they are purple. Pull them into the cabin, and hook them to the back up light switch. the purple hook into a plug above the drivers right above the carpet tunnel.

Use new FW bolts.

The manual shifter uses the same bolt holes as the auto shifter.

the shift rods need to be cut and rethreaded. 2 about 4in and one about 3 1/2. measure twice, and cut once.

Here is a good thread.
240D 4-speed manual swap in 300CD


Charlie

[R Leo]

Originally Posted by ubertino

Any input from the wisdom of the crowd would be appreciated.

Search is your friend.