300d 4-speed swap: are you happy with it?
 

I've been contemplating swapping a manual transmission into my 1985 300TD for no particular reason other than why many of here seem to want to do it. I love Mercedes diesels, I love manual transmissions; ergo ...

I've dredged through all the conversion stories here ... kept an eye out for the elusive 300d 38# flywheel and the 5-speed euro trans ... and have finally decided that I think I'll just put a 240 flywheel in there, pop in a 4-speed, shorten the driveshaft and shift linkages, and be happy.

I have a niggling worry that I will take a perfectly nice car and turn it into a bastard that vibrates.

So my question to the group: IF you have done a 240 to 300 4-speed swap, can you post here if you have been happy with it? I'm looking for someone to push me off the edge. ;)

Thanks in advance!

-Dan

PS - holler if you have parts near SC to do this swap.

I have the 240D flywheel. Yes, at certain combinations of speed and load it does vibrate. I still like it better than a slushbox.

Hi Dan,

I'm in Columbia, and I have a 5 speed W123. I don't think I want another automatic after driving stick MB. Just a personal preference. I drove in a pristine, perfect 300D NA auto this weekend and no person in the universe could find any fault whatsoever with that car. Even my wife & daughter were commenting on how that car was sooo nice ... Blah Blah Blah. LOL. However, I would say that even though it was a perfect ride, I would stick to my stick vs. go back with the auto.

As for a few "tricks",

1. Grab from the JY the 4 prong plug which is your NSS and reverse light. I made a jumper for the NSS. Nice little plug in. Avoids a lot of wires and mess, at least for me. I am looking for the 2 prong wire that hooks to the shifter for rear lights.

2. Get limber ... It was a PITA to get under the dash and hook up the pedal assembly.

3. Try to get a "master list" of all the conversion issues. There aren't really many, but that is hind sight. While you're in the middle of things, its a PITA.

4. If it's not your DD, then no biggie and no rush to get'er done.

Wow! even your SO's could find no fault with that car! that's saying a lot, I'm glad the car went to you and not the crusher!
we did get the clip back on the brake actuator pedal didn't we?

as for the NSS, you're not going to remove the harness and link it up like was listed in the earlier thread?

for the OP...

have assistants!!! Greazzer's car was NOT a quick job!!! and both cars were side by side.

No ... I worked on another members car this weekend. He drove a God awful distance for a quickie and his car is, according to my SO, a MERCEDES. Don't get me started.

My hood is scheduled for a repaint and hubcaps and a few other things, BUT according to my SO, you are better than MR. Goodwrench so don't get me started on that either.

Right now, I am not even worthy of a 3rd stringer compared to others now ...

I already did the mod'd plug. I really like it, much neater and fool proof. AND, you are correct: purple/violet and purple/violet with white line. Works like a gem !

AND -- VSTECH worked magic in about the equivelant of 2 days. Dont let him fool you ! He just made me pay the price for my insolent tone !!! LOL

thanks!
 

Thanks guys ...

I think me doing this job is pretty much inevitable. The car has been a daily driver but I have a number of others to drive (see signature).

Thinking now about whether to source parts and get everything gathered together so I can do the job at once or get a donor car. I have stumbled upon a local 240d manual but I have a feeling I would hate to tear it apart and would wind up with yet another car and no manual trans in the 300td. And, my time is limited so it may be worth it to get the parts pre-pulled. But, I know that would likely leave a jigsaw puzzle to get everything into the 300td.

Greazzer, I'm jealous of that 5-speed! Cool stuff!

-Dan

I'm about to do this swap, I just discovered I still need a couple small parts but I'm getting pretty excited about, especially since my slushbox is getting pretty slushy lol

I have a 85 300d with a 4 speed from an 82 240d. I bought the car with the swap in place, so I can't speak to the conversion process. I have noticed a few things about the swap that I can pass on. First, the car is much more fun to drive than an automatic and from my limited experiance seems to get better milage. I've noticed that the gearing leans towards high speeds rather than having a very low first gear. I expect that the rear axle ratios were significantly different between manual and automatic transmission cars. This results in keeping the car in lower gears longer. 20-35 mph city traffic is 2nd gear range and 4th gear really isn't comfortable until 55 mph or above. It is almost, but not quite like having a 3 speed with overdrive.

Other things I have noticed that may be peculiar to this conversion include the lack of a safety switch to prevent the car being started in gear, somewhat finicky shift linkage adjustments, and some under dash electronics being poorly relocated to make room for the clutch.

you probably know this; replacing an auto with a manual transmission should require lengthening, not shortening, the driveshaft.

I loved my euro 300d....the four speed was fun....though it wasn't fun when I first got it....learning to drive a diesel stick as your first manual car....wasn't fun specially on hills. I loved the sporty feel to it....it eventually needed a clutch and trans rebuild....after all the windows got smashed I left it....where it is at is any ones guess....one day I hope to stumble across anther. The euro 300d's are built sooooo much stiffer and better then the us versions.....all the us versions are all luxury and no sport...

When I did my swap in the 85, I didn`t have a donor car, I just sorced my parts from PNP. had everything I needed since I had poured oved a ton of 4-spd swap threads.

You won`t use the automatic front section of drive line and lengthen it, which I think is 13 inches. you use a 240D front section, and shorten it down to....I think is 19 3/4 inches.....been a while...measure twice, cut once. think the driveline work was like $300.

Everything is pretty much plug and play, MB makes it real easy to do the swap.

I agree with what Scottytech said how his car is, mostly 2nd gear around town, and out on the Hwy above 60mph in 4th she runs good. drop below 3000 - 2800 RPM`s and drop into 3rd or you will feel her lugging or some vibs.
I did pick up 3mpg which was great. It will be a totally different car when you get through.

The night I finally got the damed clutch finally bled, I backed it off the rmps and it was like a rocket. that reverse is geared high. probably has something to do with the 2:88 Differential the 85 uses.

I finally found a 617 38# FW I will eventually get installed, and that is suppose to smooth things out some.

One thing I noticed, you can get rid of a lot of the linkage on the VC and it will feel smoother. less pressure to push the peddle down.

Go for it. :)

When you get your project finished you can join the exclusive club:
"W123 300D/CD/TD Turbo Diesel Manual Transmission Club".
http://www.peachparts.com/shopforum/groups/w123-300d-cd-td-turbo-diesel-manual-transmission-club.html


Charlie

I've had one of each, a 240 fw and the 300 fw. Neither has enough vibration to sour the results. The 240 just has a little more, nothing to get excited over.

With the 307 diff in my car, if you shift into fourth gear under 40 the engine will buzz everything in the interior. Around town you just never need more than the three lower gears. Fourth for the higway and fifth if you have it is for after reaching pretty much cruising speed.

donor car
 

So, I went and looked at the potential donor car today ... 1983 240d 4-speed ... half afraid I would wind up with yet another car that I liked to drive instead of a pile of parts. Car has 400k+ miles and has seen only absolutely necessary maintenance in recent years. Significant blowby, probably hard to start when cold (it was warm when I got there), drivers window regulator broken, electric sunroof not working, non-functional HVAC, bad engine mounts, all the usual things.

But, the trans shifted smoothly and made no noise, I didn't see any rust. Decent interior. Had a new radiator, battery and alternator. I decided I wouldn't feel bad about using it as a donor and parting it out. Guy was asking 1350, I offered $1000, we shook hands on $1100, bring cash and get the car next day. Guy sends me an e-mail, says wife wants $1175. Grrr. Part of me wants to say that I was already giving too much for a clapped out 240 and I'd be better just hunting a pile of parts.

I'm jealous of all you guys with the pic-a-parts -- we have none here and most junkyards either only have 2000 and newer or act like they are dealing in gold artifacts.

-Dan

If you're set on 1100, don't be afraid to walk. Tell him you can come over with 1000 or you will find another car.

You made a Gentlemans agreement by shaking hands, and that sealed the deal on a dollar amount. A mans word is a mans word.

Who cares if it causes a Divorce, that`s his problem. :D

400,000K miles is just barely broken in, that is the 1,000,000 mile engine ya know. :rolleyes:

Charlie