Limited Slip Differentials for W124's??
I'll second the recommendation for four new snow tires... Blizzaks are great, but any "real" snows are better than "all season" rubber for ice & snow use.

im guessing e420 exles with same year s-class diff
correct me if im wrong
As context, I have a totally stock 1987 300td without asd or any type of traction control (it does have abs). It's been my snow car for the past 6 years, driving from CT up into NH and VT on weekends to ski (i.e., when it snows hard, i'm the first on the road instead of the one sleeping in). I run it on a good set of 4 snow tires, which make the handling/braking fantastic and predictable in the snow, and it hasn't ever gotten me truly stuck (even on nh and vt hills although I have to keep the momentum up of course). The car is in great shape with minimal/no rust (yet - it's originally from FL) and so rather than get something else i'd like to increase the utility of this car. I'd like a bit more confidence in getting moving when the snow is deep or i'm on a hill, and the only thing i can think of would be a locking or limited slip diff. I have a well-trusted independent mechanic, and he'd be doing the work.
So, given that most of this thread is about coupes and gas cars wanting to run a faster quarter mile whereas i'm more interested in turning my mercedes into a subaru...
1. does the basic idea make sense, and do you think an lsd would make my car significantly more useful in snow? the tires have to spin a bit in order to dig through the snow, i just want them to spin together. is there a disadvantage other than $ (i hear lsd's can cause you to slide more as both wheels tend to break loose rather than one, but that doesn't bother me so long as it remains controllable by moderating the power)
2. is there an lsd i can buy and install in my 1987 diesel wagon that doesn't require modification, ideally from the factory? is there any way to get that 100% lockup under 19mph, or would it be just the ~35% lockup (i assume my not having ASD impacts this)? my main concern is getting going from a stop and keeping speed up while climbing a hill (currently i look in the rearview mirror and often see a single rooster tail shooting out from one side of the car).
3. should i expect to pay 1k to 1.5k for the unit and installation?
4. any other ideas or suggestions (besides buying a subaru - i like my diesel a lot)?
5. off topic, but someone was mentioning suspension - is there a stiffer set up i can install that doesn't lower ride height (ideally, it'd increase the ride height a bit)? i bottom out the front end on occasion when bombing around snow-covered VT hills.
not directly related, but to get in on the snow tire discussion: i have had great luck in all types of snow and ice with studded Nokian hakka 2's (currently the hakka 5). probably less good on dry roads than the blizzak, but i think they're the best tire you can have for the snow on one of these cars. they totally transform the level of control you have, and i often find myself cruising at 60+ (when no cars are around) in 2-4 inches of snow with good directional and speed control.
Thanks.

Probably not, unless you can locate a used one to rebuild. A new one is $1640 MSRP, lowest price I know of would be about $1150 to your door. Plus new bearings, seals, fluid, etc figure a solid $1400 in parts, plus roughly 10 hours labor (maybe more). You could reduce the labor by removing the diff from the car and taking it to a rear end shop to have the LSD installed; or ship it to WhippleM104 (dealer tech in WA) who might be willing to do it for you at a fair price. Figure closer to $2k with a new diff & labor. Now, if you could find a used one (typically $300-$500) and rebuild it (+$300 in parts, plus labor) that might shave ~$500 off the total, getting you back near $1500. This is what I did, btw - photos are here.
) come of it. thanks again.
The Best of Mercedes & AMG
"Germany has 15 on order with an expected release date in middle of February - but don't count on it. Bad news is that date always changes; the good news is they will eventually get them."
LSD = 35% lockup (max, when new)
ASD = 35% lockup (max, when new), and 100% lock (max) when ASD is engaged
Put another way, ASD is based on a standard LSD, but adds hydruaulics to fully lock the diff when the ASD computer says to (under 19mph). Details are here. ASD is more desireable than LSD; but it's difficult to retrofit if the car didn't come with ASD from the factory... in that case, LSD is the easiest option.
The percentages gradually reduce over time as the internal clutch pack wears. When the internal clutch pack is worn out, ASD will have very low lockup (say, <10%) even when ASD is engaged, and even less (near zero) when ASD is not engaged. A new clutch pack (~$300 in parts and ~10 hours labor) will fix that.
Well, I think I'm going to need some clarification on all this.
Aside from welding and a quaife...
Would I be able to stick an LSD from a cosworth into my 92 CE? What would be the absolute easiest route to do an LSD on my coupe?
PM me if you want more info.
I have a US-spec 93' 300E 2.8, but I am located in Europe.
According to the chart on Dave's site, both 3.06(Euro M104) and 2.65(US M104) use the same LSD carrier (126-350-40-23).
Does it mean that all I have to do is find a Euro 2.8/3.2 W124 with ASD and replace the main gear in the diff with my 2.65 gear before installing it in my car?
In fact I'd be happy to source a cheap Euro M104 parts car with ASD and swap the whole system to my car altogether to get full ASD functionality. Is this possible, while maintaining the stock 2.65 gear ratio?
I want my car to be the perfect, quiet autobahn-cruiser with some added traction on snow/ice.
http://mbspecialist.com/mercedes_web.../?q=1263504023
The Quaife runs around 775 GPB direct from the mfr, and has no clutch packs to wear out:
http://www.quaife.co.uk/shop/search/results/qdf5v
The PN is 124 350 93 14 (REAR AXLE HOUSING WITH DIFFERENTIAL; MAN. 5-SPEED/AUTO 4-SPEED TRANSMISSION
ASD 1:3.06) for the whole differential assembly.
Here's one for sale in Germany:
http://cgi.ebay.de/ws/eBayISAPI.dll?...#ht_1581wt_905
Does this change anything?
I value Your opinion greatly Dave and thank You for such a quick reply. Perhaps, what I've written now gives some new light on the case?
One more thing. 2.82 seems to use the same carrier as 2.65 and 3.06. 2.82 is what W140 350SD used. There is such a diff for sale on my local listing (W140 350SD ASD). Will that fit as well?
Last edited by MaxMatt; Feb 23, 2011 at 11:16 PM.
I'd still recommend the Quaife if you can afford it, but the factory LSD is fine for normal street use. You could take a gamble on a used unit having enough life left in the clutches to last a while longer but if you install it and find out the clutches are shot, then you have a lot of re-work. Basically depends on how much time and $$$ you have!
And yes, the same LSD carrier (126-350-40-23) fits several diffs, including the S350 ASD. However the diff housing, flanges, and rear cover may be different on the W140. If you are just buying it to get the carrier, that's not a problem. If you intend to try and swap the complete differential assembly, get one from a W124 with the same flanges & cover to make it easier.
With just swapping the carrier, backlash and preload should be checked, but on all the LSD's I've built so far, it was close enough to spec that adjustment wasn't really required. They were all just a hair out of spec but some adjustment shim thicknesses are no longer available from MB, and I didn't feel like trying to have a machine shop modify a thicker one down to 0.05mm accuracy.
Usually when re-using the original shims (don't mix up left & right!!!) it ends up with the backlash being just in spec and preload being just out of spec (slightly loose). The diffs have all worked perfectly and are quiet, zero gear whine. The photos on my website show how to measure the backlash & preload using home-made brackets and a dial gauge.
http://www.w124performance.com/images/W124_diffs/
If you are thinking of rebuilding a used one, here is the FSM procedure:
http://www.w124performance.com/docs/...ebuild_FSM.pdf
I looked at the photos numerous times before, but I still don't understand any of the measurements or how they can be adjusted.
Still - I understand that to avoid all the really tricky stuff I will be better off just fitting my ring gear on the LSD carrier and swapping it into my diff. Do I understand correctly?
The final question is whether my diff with LSD carrier will be able to work with the ASD system from the donor M104 car?
This is the city, where I live:

Just below the mountain on the right. Most of my neighbours use 4x4s in winter, but I'd prefer to use my W124, which is a much better cruiser.
I'd like to retrofit the whole ASD system from the donor 320E with working ASD into my car. Everything - starting from the diff, pump and control module and ending with the dash traingle light
However, a fresh LSD unit should work just as well... the ASD, IMO, just helps compensate for clutch pack wear (to a point) by applying additional pressure to the clutch pack. The really nice thing is the dash warning light as this gives you visual notification of wheelspin before you can even feel it. Very, very useful on icy roads. But for pure traction, slap on a set of studded Hakkas and with LSD you'll go just about anywhere even without true ASD. The ASR system is even better. Now that I've got a couple of E420's with ASR as daily drivers, I'm sold on ASR for winter use. It's plain awesome.




