MB four speed transmission
 

I have several 4 speed transmissions from PNP trips. I may also be able to put together a full W123 swap if someone wants one. Let me know if you are interested I figure $250 for a trans, $450 for a swap kit. If you are local I may even be able to do the swap, BUT, I will not garauntee the 1800-2200RPM vibe will not be there. I havent completely solved this on mine and I dont know anyone else who has either (300 turbo). If you want I can demonstrate the vibe on mine and see if it is something you can live with.

A driveshaft harmonic problem?

my firm belief is that there is a harmonic in the engine trans mount configuration that cant be solved by laymen. there's probably a good reason MB never put 4spds in 300 turbos. my guess is the NA need to operate at higher RPM since they do not have the power to even try to push the car at 1800RPM. as long as you are above 2000 RPM there is no vibe.

The very heavy 300d flywheel and the extra little mass around the flex joint at the tranny make it very very slight.

The 300 with a 240 fw and no extra mass at the flex vibes more but not enough to make me want an automatic!:P

me too, once you get used to the 3200RPM shift points the car is a blast to drive, heck it will even outrun a lot of the 4 banger ricers. I need to take the car out and do a 0-60 run. I know its pretty good with the gear I have now.

kit would include:

4spd transmission and bell
clutch
pressure plate
pressure plate bolts
240D flywheel
240D auto crossmember
flywheel bolts (used, manual recommends new but I reuse them once)
w123 full pedal assembly with master cylinder
slave cylinder
hyd line from master to reservior (these are generally rotten but the new part is $5
hyd line from master through floor
hyd line from floor to slave
W123 4sd shifter, rods and clips. I can shorten the rods if you want for the 300D
I will try to get a speedo cable, yours will not be correct length
wire harness from shifter (reverse lights, you will lose nuetral safety)
you will need to shorten the DS for a 300D. I can get one shortened for you for $75 plus cost of DS (should be around $20) it is recommended you do your own and balance the whole assembly together

I'd love to buy a kit! but I have a w126, if you can put together a complete kit for a 126, then you got a customer.

$450 is expensive without the necessary cut driveshaft.

Your firm belief is wrong. My car is living proof of that, NO vibration! :D

Nope. The difference between the euro non-turbo 617 and the turbo 617 as far as the drivetrain can tell, is nothing. The USA got all the turbo engines and you and I both know MB thinks power-hungry Americans are too stupid to drive a stick.

no one sells a kit with cut driveshaft and cut linkage for $450, thats what it is worth to me, if it doesnt sell then I wont spend the time to build one up.

I have seen 10 posts of people with vibes and one (yours) who have it fixed. the vibe is caused by a harmonic and it is on the engine side as it is consistent with RPM. if your cure was completely valid it would be repeatable. Please give us the recipe :)

I dont know MB's thinking you are correct. but are there turbo 4 speeds out there? and my turbo starts boosting around 1800 RPM, so there is a difference as a NA would not almost push the car at 1800 making it seem to this stupid american that I can run lower RPM. surely someone could have ordered one if they were available. In reality it shouldnt even be a problem if you shift at 3200 you wouldnt even know it was there

Im not sure there is any difference? if the pedals bolt in you should be fine. Take a few pictures under your dash up at the pedals and I will compare it to the W123 and W201 pedal sets I have to see if one of them will bolt up I remember asking the guy who did an SEC diesel conversion and he used the W123 pedal set, I dont remember if he had to modify it or not.

I think the pedals need very slight modification to fit the W126.

thanx, any info you have would be appreciated. my long term goal is to convert an SEC to a diesel 5spd

I have a factory Euro spec 1985 280SE with the four-speed. I would be willing to post some pics when I get a little time if anyone is interested. I am also considering selling the car.

Aaron

The w126 has an electric speedo. That is more difficult to get working with the 4 speed 240 trans.

yeah but I am surrounded by electrical engineers at my work, so Im pretty sure I can duplicate the pickup in the trans

Simple, don't lug the engine by running at such a low RPM. :)

With the stock turbo the torque peak is around 2800rpm. Even with a VNT the torque peak is 2000-2200rpm.

vibration causes
 

I know on some of the older Mercedes the crank and the flywheel were balanced as a unit. I have balanced flywheels before. You need a lot of special equipment, so it would need to be done at a shop that works on driveshafts and such.

What I am saying here is that perhaps the problem with the vibration is coming from the change over to the 240D manual shift flywheel from the 300D auto shift flywheel.

I know what type of job it would be to tear down the car to do this, but you might consider trying it out on a future conversion, or if anyone else here does one they could try it out and report their findings.

If you have the equipment it takes about 10 minutes to balance a flywheel/ring gear combo so it should not cost that much if the flywheel is out of the engine.

Pooka

I just picked up a 300D with a bad trans and need to get it drivable ASAP to do some prechamber tests. I don't want to spend time on the automatic and the 5 speed bell housing project is not far enough along for me to wait.

Do you have a "kit" available? Please PM me with .
details.

Side note: I have been out of town and will get an idea of the casting pore cost this week.

thanks

any kits left where are you located?

how about the drive shaft, what do I need to do for a driveshaft in a126?

Hey lutztd, do you still have a kit available? what was your price for everything? Including the drive shaft? This would be for an SD. I am very interested! My poor benz is on blocks waiting for a manual.

sorry no, I have about 80% of whats needed. I will watch for a car, but the kit I have is missing components and I want to offer a complete kit rather than piecemeal. when I posted I knew where a car was but when I went to collect some of the parts the shifter was bad and the trans was full of muudy gunk so I assumed the rest was in equal state of repair and I left it. I will post again when I have a full kit.

I have a spare tranny I just pulled out of a W123 that works fine. $ 175 and it's all yours. I'm in the metro Detroit area. Just picked up two more cars to do surgery on, so you can send me a private e-mail if you want the trans. I'll have more coming in March.

I was going to put a 240d and AT in a 170D but that's too much work, easier to pout the stock OM636 therein.

s

I may be interested in a kit. I just bought a 82 300D and the tranny is slipping. I'm going change the fluid and filter and try to get it working properly, but would prefer a stick anyways.

I live in South Dakota, and there are very few Mercedes cars in the area, much less any in the bone yards.