Differential options

[Adam230K]

Ok now we've removed the differential which happened to be an open diff, quote alot of the teeth were missing and there was metal filings dropping on the floor, and some of the actual gears were very loose... so glad it didnt break while i was driving.

Now lies my next question:

Before i contact dronsfield on monday to negotiate another differential i want to know what will be involved in fitting a limited slip differential or as the parts' technician called it "Anti-lock diff/ ASR"? The technician told me they have exactly the same ratios but that the ASR one had more sensors and needed appropriate wiring, and it was usually done in the factory before the car was to be sold.

Now he showed me the ASR diff and it looks exactly the same, same casing/housing, same design, and its the same ratio! just a few more sockets probably for electronic aids ( i think like 1 ).

My question is, can i directly replace my old open diff, with this limited slip diff? and if i could, how would i get it to fully function like on any other merc similar car? is there alot of work involved?

I would like to know the answer to this before monday, cuz if i can upgrade something like that for not much extra, i'd love to do it. Any help / knowledge shared is much appreciated.

 

[Ian B Walker]

Not sure what is involved but will put mine up on the ramps Monday and have a look. I rather suspect that there will be quite a lot of wiring to do and also a different ABS unit. Mine is quite large, larger than a normal one, with plugs and wires coming from it

 

[grober]

Not really a practical retro-fit

The normal ABS system on the W124 has a single sensor on the differential-for an ASD sensors are required on each hub for starters . As Ian says its operated through a modified ABS system- think of it as a half way house between ABS and ASR without the electronic engine throttle actuator. The ASD or automatisches Sperrdifferenzial to give it its full title is an electrohydraulically operated automatic locking differential using multi-plate clutches giving a variable locking effect from 35 to 100%. In a normal installation its designed to aid traction when starting in slippery conditions and only works up to 19 MPH so is not really a performance cornering aid. It would be prohibitively expensive to install as a retrofit since some extensive addition/modification to electrical circuitry is required. Your best bet would be to fit a self contained viscous coupled type diff. I believe AMG offered this type of modified diff at one time but was about £3k at the time. I have a feeling one of two members here have done this type of mod so hopefully they will chip in.

 

[Number_Cruncher]

>>is an electrohydraulically operated automatic locking differential

Yes, if the info I have is applicable, there's quite a bit of extra hydraulic plumbing involved too - with extra valves, and a dedicated accumulator mounted just ahead of the axle.

The electrical, hydraulic, electronic, and ABS changes required really put this system beyond being a retro-fit option.

 

[Adam230K]

Ahhh i thought it would've been a straight bolt-on. Ok thats fine, i ordered the like-for-like differential just to get it over and done with. Thanks for your time guys.