722.3 rebuild with 722.6 Internals?

[jonbobshinigin]

I am looking to rebuild my transmission in my 1987 300TDT (US) with om603. I am in the process of increasing power by installing larger Turbo, Euro Exhaust Manifold, 3" exhaust, intercooler, and modified Pump. My transmission/gearbox is in need of a rebuild and I need it to be able to handle more HP and torque. No one in the US seems to know anything about this...does anyone know if I can put any internals from a 722.6? Which parts?

[napa]

TH400...

[jonbobshinigin]

I am looking to bolt something up directly. My goals are only 250-275hp. Would a TH-400 bolt right up? Modulator valve?

[napa]

My goals are only 250-275hp.

ok.
722.3 is 400 Nm transmission...

first i think you need 1000 hp transmission

[jonbobshinigin]

Correct, but with internal components from a 722.6, it should handle abouy 785nm. I just need to determine if this is possible. I've only "heard" that it can be done.

[veskola]

forget that 722.6, it's electrical gearbox.

To get enough torque handling capability from 722.3 there is need to add more "friction plates" or what ever those are called. Same parts can be used what there there is used in mercedes 500 vehicle/722.3 gearbox.

How to do that modification and is there need to do something else, most probably yes but i do not have instructions to give. My recommendation is to contact some automatic gearbox professional and give some tips to use 500's parts and add mode plates there.

If i remember correctly there is used up to 5 friction plates for one gear.

Here in Finland there is professionals in this business. They are able to do several tricks to increase torque handling capability, some of those are secret.

[XUX63]

To get enough torque handling capability from 722.3 there is need to add more "friction plates" or what ever those are called. Same parts can be used what there there is used in mercedes 500 vehicle/722.3 gearbox.

If i remember correctly there is used up to 5 friction plates for one gear.

You can get some parts made from steel from 500-series and might also be in Porsche 928, I'm not sure about. 7 friction plates for 3rd (K1) and 6 for 4th (K2) is quite normal I think. Other tricks to brake bands, shift-kits and what ever to the valve body, you should consult professionals like JarkkoS or order a finished gearbox from him

[JarkkoN]

I am not an expert on this but this is roughly what I have heard:

The original 722.3 in your TDT can handle 400 Nm. It is the strongest
gearbox of that time and its has been used in V12 and AMG models
with different friction plates and adjustments (and perhaps someting else).

You can adjust the gearbox yourself to make shifting stiffer and avoid
slipping when torque above 400 Nm is applied. Illustrated instructions are
available on the internet in Finnish and it would be a small task to
translate it in English.

722.3 can handle 600 Nm provided that the number of friction plates is
increased inside the gearbox. This requires special skills, however, any
sophisticated gearbox professional should be able to do this. No
instructions on how to do this are publically available.

You might ask a professional to istall the friction plates of a V12 or
AMG model on your gearbox. They should fit, if is the same 722.3
gearbox in both cases.

The number of horse powers can be obtained by myltiplying torque by the
number of revolutions per minute. Typically, Super Turbos use higher
RPMs than standard TDT. The given target of 300 hp requires
strengthened gearbox. By simple DIY gearbox tuning you may be able to
handle about 220 HP without slipping, which would eventually burn your
gearbox friction plates.

[jonbobshinigin]

Thanks so much! I have posted information all over US forums without getting any REAL info.

[JarkkoN]

Mercedes Benz Transmission Application:
http://www.europeantransmissions.com/Application.htm
http://www.europeantransmissions.com/Application.2.htm

300 TDT 1987: 722.317
S600 1995: 722. 362

I could imagine that a rebuild kit for 722. 362 would fit on 722.317 (ask a
professional). S600 has got 580 Nm torque, which would be enough for your need.

Model specifications including torque and HP:
http://www.mercefreaken.com/

You could probably find a second hand transmission for a V12 (S600)
for couple of hundred dollars in your home town. Fitting it to your TDT
might work easily, but I am not sure.

Here you can check the spare part numbers and see drawings of all car parts for comparison purposes:
http://www.auto-parts.spb.ru/cat/cats/m ... ent=dr2000

[jonbobshinigin]

Would an S600 transmission be a direct swap? There is one locally on Ebay:
http://cgi.ebay.com/ebaymotors/MERCEDES ... ccessories

It has 140K Miles and is from a 1992 W124 S600 V12.

[JarkkoN]

For more information on 722.3, check out this diagnosis manual for all 722 gearboxes:

http://w126.pp.ru/akp722.pdf

About the eBay gearbox: You need to ask the part number of the gear box
or at least check if it is a 4 or 5 speed gearbox. We are not so sure about
the specifications of North American versions here in Europe.

I suppose there could be some differences, such as different flanges.
If so, the flanges can be swapped from one to another, I think. But I am
not an expert on gearboxes.

What seems to be the trouble with your old gearbox? Perhaps it's a minor
issue which could be treated by your self. You could also adjust the
gearbox stiffer and then drive the car for some time before you really
need the enforced one.

[jonbobshinigin]

What would it cost to have someone over where you are to have a 722.3 modified for high hp?

[Sergey]

i'd say roughly 1000-1500USD. ca 1000 euros?

[AMG Dave]

The info posted above is correct. The 722.3 can be built to withstand a serious amount of power... it survived behind not only the M12 V12, but also the 6.0-6.5L M119 monsters from AMG, RENNtech, and Brabus, and also the 7.4L M120 V12 beasts. And some supercharged versions too. All have well over 400 lb-ft of torque, some possibly over 500 lb-ft.

BlueRidgeMB in Atlanta, GA is able to add the extra clutch packs to the tranny. I am not sure exactly how to accomplish this. I believe you can also get the primary drum (??) from the SL600 trans which is reinforced compared to the non-V12 trannies, but the cost new is $$$$, and it would be a shame to part one out just for that. You can't use the V12 trans complete as the bellhousing pattern is different - won't bolt up to the non-V12 engines.

My plan: Drive the stock tranny until it kerplodes, then replace it with a beefed-up version. Same for the differential.

[Alastair]

On my ever complicated quest for a transmision, Ive gone from thinking Auto, to Manual--and cant find any suitable diesel trans either manual OR Auto....

So, I'm re-looking at Auto....But Now from Gasser!

Most 'robust' type I can easily get hold of that isnt going to cost the earth, is 722.369 --from 3.2L M104 W124 car--This engine developed 310nM torque, 220 BHP

Looking at it, I'm fairly sure I can adapt it to run with OM.606, if I add Vacuum Modulator to I.P.
(Transmission doesnt 'care' what fuel the engine's using after all!)
--Issues will be Torque and Where in rev-band its developed in comparison to what that trans was designed for--May have to find proper Diesel Torque-Converter though....

Ive been investigating the internals too. It appears that to accomodate extra friction plates and 'steels' they have different thickness plates, and No spacers.

They are available in three thicknesses. 3mm 4.5mm and 5mm.

Choosing the thickness and number to fill the available space in the clutch pack....

I'll post more as I find more out....

[Easy Rider]

Most 'robust' type I can easily get hold of that isnt going to cost the earth, is 722.369 --from 3.2L M104 W124 car--This engine developed 310nM torque, 220 BHP

Looking at it, I'm fairly sure I can adapt it to run with OM.606, if I add Vacuum Modulator to I.P.
(Transmission doesnt 'care' what fuel the engine's using after all!)
--Issues will be Torque and Where in rev-band its developed in comparison to what that trans was designed for--May have to find proper Diesel Torque-Converter though....

Aren't those all 722.5 trannys in W124s with 320 engine? If there's been 722.3 tranny available in those, it's surely better box for diesel than 722.3 from 300E (incl.-24) models. Highest values in power and torque are ~1000rpm lower on rev-band. 320 has also little more torque than older versions with ancient distributor ignitions and mechanical injections.

I haven't heard of 4speed trannys in 320E models, but if there is that option, i 'm interested. That could be a good transmission for my 190E 3,2-24. Now there is Getrag from 2,3-16, custom steel flywheel and 250mm clutch from Sprinter, i don't want to mess with the electrics of the 722.5 or put a tranny that doesn't fit right on rpm-scale. Exactly when was that 320E+722.3 combination available and what was the diff ratio on it?

[Alastair]

Have a look at this chart-

http://www.europeantransmissions.com/Application.htm

It lists various models, and the transmissions etc....

Personally, Ive never owned a W124 or any Gasser M.B. (Except an ancient W114 280E) so have little knowledge of the gasser variations or models....

I stick to W123 300D....

I 'chose' this transmission as I can get one at reasonable price complete with converter and a warranty-of sorts, and its Not electronic, has a 'Vacuum-dependant' shift modulator and no throttle-cable connection. Kick-down is by elect switch, just like my current 722.4 in my W123 300D, and it will bolt-up to my OM.606 engine....

There were only electronic 722.6 300 Turbo-Diesel transmissions here, and the 300D W124 has 722.4 --which aint up to much!

[Roisto]

Hi all,

Yes, there has indeed been a 4-speed automatic for M104. When I've browsed through the WIS & electric circuits, I've come to a some sort of a conclusion that the 722.5 was not very common in US (at least in 124). The electrical manuals in English only show the 4-speed versions. Alastair's link only makes the hunch stronger. It might not be very easy to find one here in Europe, though.

The 4-speed has the same diff as the 5-speed manual (3.06 or so). The 5-speed automatic has a "slower" diff (3.69).

BR,
Risto

[BuuBBa]

Damn, MB:s haves too much different aut. transmissions

I`m planning to get a new car, but still not sure what model.
CLK 430 / 500 (W208)
SL 500 (R129)
C43 (W202)

One thing is sure.. I will install a supercharger or turbo, so power would be somethin between 400 and 500 (depending on what base motor will be). This also means that the torque will raise to +600, maybe +700nm, so what transmission (and same time, what car has it originally) would be the best choice?

Is it just a legend that AMG have made some modifications for C43 tranny?

Thanks for replys!

(En oikeen löytänyt foorumilta tietoa, niin ajattelin kysyä valmiista topicista)

The 4-speed has the same diff as the 5-speed manual (3.06 or so). The 5-speed automatic has a "slower" diff (3.69).

BR,
Risto

What do You mean about slower diff? That 3.69 would rev more than 3.06, so how it is slower?

[bolide]

Most M104 engines used the 4-speed auto which is a hydraulic box. The 5-speed is a similar box with an additional overdrive gear train operated electrically by a solenoid

These boxes predated the electronic boxes of the W210 series and don't have an ECU as such. The 5-speed does have a control unit that picks up a speed signal from the speedo plus various other sensors and the gearstick switch to operate the 4-5-4 shift

Based on cars I have sold these are the part numbers

M104 E280 4-speed transmission 722433
M104 E280 5-speed transmission 722505
M104 E320 4-speed transmission 722369
M104 E320 5-speed transmission 722503

Nick Froome
http://www.w124.co.uk" onclick="window.open(this.href);return false;