Yep, I'll post a link when I get it scanned. It would be possible to add "manual" ASD, triggered by a switch on the dash. Or even a fully manual trigger with a hand hydraulic pump (saw that done by a guy in Europe, I think). But to retrofit the full ASD system, that would most definitely be a challenge (and probably quite expensive). You would need the ASD brain box, wiring harness, speedometer, and all the hydrualics & valving. My '93 300D has factory ASD, btw. However, the ASD still uses the standard ABS system with a single rear speed sensor... only ASR has the dual rear sensors (my V8 models have ASR).

While I really like factoy ASD, I believe it would be too difficult retrofit, unless you had a complete ASD donor vehicle to snag ALL the parts from. Even then, I am not sure what the challenges would be. All I wanted was to eliminate the "one wheel peel" on wet or dirty pavement, and plain LSD has cured that (at least with fresh clutch packs installed). If you buy a used ASD diff, it's almost guaranteed to need new clutch packs.

While converting to plain LSD is not simple, it's much easier than attempting a full ASD retrofit. The cost to convert to LSD is at least $750, plan on more like $1000, including the new clutch packs, seals, fluid, etc. Those numbers do not include labor, that's parts only. I don't know what it would cost to do ASD but I would figure at least $300 more plus a LOT more labor.

Link to PDF of factory brochure explaining the function of ASD, ASR, and 4MATIC - click here.

YIKES! That sure doesn't sound easy. So if I just switch to the LSD and not all the electronics, it would give me 35% lock up, if I rebuilt the clutch packs, is that correct? Would I still need to hook up the hydraulics?

Does my wagon and the 90-93 sedans have the same rear differential?

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1987 300TD 309, xxx 2.8.2014 10,000 mile OCI


Be careful of the toes you step on today, as they may be connected to the ass you have to kiss tomorrow. anonymous

“Be who you are and say what you feel, because those who mind don’t matter, and those who matter won’t mind.” Dr. Seuss

Does anyone know if a differential from 1992 4 matic will work in an '87 300 TD?

__________________
1987 300TD 309, xxx 2.8.2014 10,000 mile OCI


Be careful of the toes you step on today, as they may be connected to the ass you have to kiss tomorrow. anonymous

“Be who you are and say what you feel, because those who mind don’t matter, and those who matter won’t mind.” Dr. Seuss

A manual ASD install would be possible for someone experienced and knowledgeable but not an easy job. I know in the factory installation it is powered through the OVP (asd cars tend to have a different ovp relay); also there is a switch on the brake pedal which activated and presumably cuts out the ASD operation for some reason.

Have a look a the video I posted on the first page to see it in action. You don't strongly notice it activating. The only time I notice it is if it's wet and I pull away at speed inducing wheelspin. When you hit a certain speed (19mph by the looks of things) the acceleration occuring can reduce - this is I presume due to the ASD cutting out and me being left with less rear lock up and less traction.

In the dry, in bends, and making a tight turn while pulling away, I don't notice it operating, so either it's quite subtle, or the existing LSD effect is making a good difference already, or my clutch packs are worn out.

Incidentally my ASD diff has slack in it and makes the drivetrain clonky; is it rebuildable and could I do it myself?

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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg

The clutch pack is rebuildable, and is an "advanced" DIY if you're willing to tackle the job. If the diff itself is worn (bad bearings, or gears, etc)... forget it, much easier (and cheaper) to replace with a good used diff.

Let's hear more about the rebuild.....
Can it cure looseness in the diff? Cure jerking at low speed and changing gear?

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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg

The rebuild is pretty straightforward, and covered in the factory service manual (the W126 manual has really good photos of the procedure). If the diff is "loose" as in sloppy, meaning excess gear backlash, or bearing movement... that's when you replace the entire diff with a good used unit. The clutch pack rebuild ONLY will improve the limited-slip action. When the clutch pack is worn out, the diff acts like a plain open diff. Rebuilding the clutch pack restores the limited-slip functionality only.

Jerking at low speed and/or when changing gears sounds like a tranny issue, or flex disc problem, and if it is the diff... again, that sounds like a worn-out differential. A tired LSD clutch pack would not cause any of that behavior, it simply wouldn't provide any connection between left & right wheels.

In LSD work I've done, I was able to specify how much lockup (what %) I wanted, I've gone up to 60% for some racing applications.

Dave or others might know if the parts are available to create a tighter rear diff for these cars also, I'm guessing yes. Looser also.

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Gone to the dark side

- Jeff

Nope, not with the Mercedes design. If you try to make the clutch pack tighter, you cannot assemble the diff (the spider gears will not rotate into position). BT, DT. When set to spec, it immediately (within 100-200 miles of driving) wears enough to allow turning left vs. right sides by hand. It only offers the ~35% lock when under load (torque applied from engine to the wheels), this puts presure on the clutches and causes them to engage.

You can add a spring block, which adds pressure to the clutch pack at all times. This basically simulates ASD engagement at all times. You adjust the "percent" lockup by stronger or weaker springs. The only drawback is that you cannot use circlips to hold the axle flanges in place, they will float in & out. The folks who have done this (usualy the 190E-16 crowd) say it works ok though. For street use, I have not found it necessary to do this. I'm sure on the racetrack (road course or autox, not dragstrip!) it's a bigger deal.