destrux

How can I tell if a MB differential has a limited slip in it? (other than spinning one tire to see if the other one spins the same direction)

I saw one for sale on ebay for a later model W124 (for a rediculous amount of $), and I'd like to track down a LSD at the local salvage yard for mine.. but usually the brakes are stuck on and I can't spin the wheels to check them. Are there any id numbers to look for anywhere on the car that indicate it came with a LSD?... by any chance are all of these cars equipped with them? I'm new to mercedes cars...

2PHAST

There were no LSD's for the W124. The only LSD was on the 16 valve 190e.

Saijin_Naib

Doesn't that bolt up to the m103/m104 rear diff though Rick?

STLe320

I thought for sure it bolted up to the m103...but not too sure about the 104

RBYCC

If I recall the diesels starting in 1991 had an ASD unit ( automatic locking via hydraulics ) which acted as a LSD up to about 20MPH

2PHAST

ASD is not the same as an LSD. LSD would be a fully locking differential without the aid of hydraulics or speed limiters.

The LSD functionality is encased fully inside of the differential and the 190e differential is not compatible with the W124.

cap'n jasper

See this thread

2PHAST

I think that thread pretty much sums it up, but if I recall correctly, I did try to fit a 190e LSD to a W124 and ran into many problems, mainly the axels and some other issues, so the 190e diff is not straight swap into the W124, it isn't even a straight swap into other non 16 valve 190e's, as they changed the axel design in 90 or 91, so you need to install early style axels.

On the same note, both times I bought 16 valve 190e LSD's, I must of went trhough at least eight of them, as the clutch's had worn down so badly that the diff was no longer a LSD, so chances are good if you did buy one, it would be worn down and need rebuilding.

Also, you can throw out the idea of retro fitting a ASD, its cost prohibitive.

RBYCC

.....and functionally the difference is ?????

2PHAST

ADS is 100% lock under 19 mph, above 19 mph its 35% lock, but is controlled via sensors and uses hydraulic system for its functionality. The basic 16 vavle LSD is fully mechanical and is completely encased in the differential and provides 100% (or close to it, don't remember exactly) at all speeds and is pretty simple to retro fit to other 190e models.

ASD is not that simple to retro fit to non ASD equipted vehicles. There are wheel sensors, a control module and the hydraulic system itself.

I don't know of anyone who has retro fitted a ASD to a non ASD equipted vehicle.

If you already have a ASD then your good to go, assuming of course the clutch's are not worn out turning it into a open diff (common problem)

destrux

Crap. Thought I might have had a salvage yard option. Well, I suppose I'll have to make due with an open diff. Thanks for the info.

2PHAST

You could try the 16valve diff, just be ready to change the axels, depending upon what year your car is.

Wolf190

ok i hope nobody rips me for this one... what is the advantage of a LSD? other than 100% of the power going to the ground and getting sideways easier... are there any significant power gains/ drag reductions? i've been looking into for my car

2PHAST

The main advantage of a limited slip differential is shown by considering the case of a standard (or "open") differential where one wheel has no contact with the ground at all. In such a case, the contacting wheel will remain stationary, and the non-contacting wheel will rotate freely—the torque transmitted will be equal at both wheels, but will not exceed the threshold of torque needed to move the vehicle, thus the vehicle will remain stationary.

In everyday use on typical roads, such a situation is very unlikely, and so a normal differential suffices. For more demanding use, such as driving in mud, off-road, or for high performance vehicles, such a state of affairs is undesirable, and the LSD can be employed to deal with it.

By limiting the velocity difference between a pair of driven wheels, useful torque can be transmitted as long as there is some friction available on at least one of the wheels.