W123 5 speed manual Vs. 4 Speed manual- Which is longer? - PeachParts Mercedes-Benz Forum

Guano32 · #1 04-15-2009, 12:03 PM

Hi I am hoping someone out there will know this:

I am installing a 4 speed manual trans into a w123 chassi but one day I would like to replace that with a 5 speed manual (God willing).

My question is:

Could I simply switch out the 4 speed manual trans with a 5 speed manual trans? Are they both the same length? Would this effect anything with the drive shaft or rear differential? (ie drive shaft length or gearing in the dif). Also what about clutch petal placement etc - those would remain the same, correct? Are there other considerations I am over looking?

Any help would be really appriciated (since I have grown restless looking for the elusive 5 speed manual trans for these car but would still dream of owning one eventually)

Cheers!
-L

#2 04-15-2009, 12:06 PM

Nope. The 5-speed is about 6" longer, give or take a little depending on if you use an iron or aluminum 5-speed.

lutzTD · #3 04-15-2009, 12:10 PM

Quote:

Originally Posted by Guano32

Hi I am hoping someone out there will know this:

I am installing a 4 speed manual trans into a w123 chassi but one day I would like to replace that with a 5 speed manual (God willing).

My question is:

Could I simply switch out the 4 speed manual trans with a 5 speed manual trans? Are they both the same length? Would this effect anything with the drive shaft or rear differential? (ie drive shaft length or gearing in the dif). Also what about clutch petal placement etc - those would remain the same, correct? Are there other considerations I am over looking?

Any help would be really appriciated (since I have grown restless looking for the elusive 5 speed manual trans for these car but would still dream of owning one eventually)

Cheers!
-L

drive shaft length will need to be reduced and you will need the trans crossmember from a 300D auto for the 5 spd

#4 04-15-2009, 12:10 PM

Compared.

Guano32 · #5 04-15-2009, 12:53 PM

Thanks alot for your advise guys!
Could you tell me a little about the Aluminum vs Iron 5 speed -- how could i identify one from the other and on which years did the iron trans come on? Which is longer the iron or aluminum?

Thanks again!

diametricalbenz · #6 04-15-2009, 12:56 PM

There was one for sale by a forum poster.

lutzTD · #7 04-15-2009, 12:57 PM

Quote:

Originally Posted by Guano32

Thanks alot for your advise guys!
Could you tell me a little about the Aluminum vs Iron 5 speed -- how could i identify one from the other and on which years did the iron trans come on? Which is longer the iron or aluminum?

Thanks again!

the iron one looks like the iron 4 speed with an extra section bolted on, the aluminum one is shown in Forced comparison picture. You most likely wont find an iron one. I believe the length is close to the same for both 5ers, definitely different than the 4 speed.

Guano32 · #8 04-15-2009, 01:11 PM

Also the 4 speed i plan to install is out of a 300D euro w123 car -- is this trans longer or shorter than the 4 speed from a 240D? Or is it the same (both length and gear ratios)

thanks again!

lutzTD · #9 04-15-2009, 01:15 PM

Quote:

Originally Posted by Guano32

Also the 4 speed i plan to install is out of a 300D euro w123 car -- is this trans longer or shorter than the 4 speed from a 240D? Or is it the same (both length and gear ratios)

thanks again!

same part for 240 or 300, the other rare part is the 300D flywheel which is thicker and 10 pounds heavier than the 240D piece

Guano32 · #10 04-15-2009, 01:22 PM

I see thanks for the help.

if i have your correct, the 300D flywheel on this 4 speed euro car would also work with a 5 speed trans should i be lucky enough to find one. Or would i need a different flywheel if i bought a 5 speed trans ?

thanks again!

Guano32 · #11 04-15-2009, 01:28 PM

sorry but another questions re 5 speeds

was the iron one considered stronger and more durable then the aluminum one and where the gear ratios different between the aluminum one and iron one?

also if i have you correct both aluminum and iron 5 speeds came on W123 300D grey market cars, correct, allbeit the iron being the most rare of the two.

is the aluminum one also found on other car like newer benz diesels or on any gas models which could be install into a W123 300D?

cheers!

leathermang · #12 04-15-2009, 02:05 PM

Be sure to check out the different flex discs required by various situations/combos ...

t walgamuth · #13 04-15-2009, 07:00 PM

My fiver is the all aluminum one but I didn't realize it until recently. I believe the ratios are virtually identical and I am not aware of any difference in durability or rarity. I imagine the aluminum one is lighter by 10 pounds or so.

I don't know if its the same as the ones used in the 190 and 124 body cars. If it is it uses a different bell housing since the later cars have the starter on the drivers side of the car.

The one to one close ratio fiver found in the 190 16v is a getrag and features a dog leg first gear.

lutzTD · #14 04-15-2009, 07:20 PM

Quote:

Originally Posted by Guano32

I see thanks for the help.

if i have your correct, the 300D flywheel on this 4 speed euro car would also work with a 5 speed trans should i be lucky enough to find one. Or would i need a different flywheel if i bought a 5 speed trans ?

thanks again!

if you have the 300 manual flywheel already thats great, you should use it. It will work for the 4 or 5 speed.

Stevo · #15 04-15-2009, 08:15 PM

I swaped an 82, Euro 240D, 5 spd tranny into my 79 240D, 4 spd which also included drive shaft & shifter. I sold the 82 Euro 240D with the 4 spd. Easy swap with both cars present.